The MPL has afferent neuronal connections distinct from adjacent brain regions including major inputs from the auditory cortex, medial part of the medial geniculate body, superior colliculus, external and dorsal cortices of the inferior colliculus, periolivary area, lateral preoptic area, hypothalamic ventromedial nucleus, lateral and dorsal hypothalamic areas, subparafascicular and posterior intralaminar thalamic nuclei, periaqueductal gray, and cuneiform nucleus. 
Researchers are beginning to identify brain sites associated with conditioned contextual fear such as the ventral anterior olfactory nucleus, dorsal premammillary nucleus, ventrolateral periaqueductal gray, cuneiform nucleus, and locus coeruleus.
Freezing behavior induced by intra-ICd NMDA caused an increase of Fos expression in the MGN, superior colliculus, dorsal columns of the periaqueductal gray and locus coeruleus while freezing induced by intra-ICv NMDA caused a significant Fos immunoreactivity in the prelimbic (PrL) and cingulate (Cg) cortices, basolateral and medial nuclei of the amygdala, ventrolateral periaqueductal gray, cuneiform nucleus and locus coeruleus.
I-HEM also induced significant increases in FLI in the dorsomedial PAG, A7 region, and the cuneiform nucleus compared with SAL.
In this study, we explore Fos expression (a measure of cell activity) in three nuclei associated with locomotion, namely the zona incerta, pedunculopontine tegmental nucleus and cuneiform nucleus (the latter two form the mesencephalic locomotor region) in hemiparkinsonian rats. Our results showed a significant increase (P < 0.05) in the number of strongly labelled Fos+ cells in the cuneiform nucleus in the 6OHDA-lesioned cases compared to the controls after 7 and 28 days survival periods. In conclusion, we reveal an increase in the number of strongly labelled Fos+ cells within the cuneiform nucleus of the so-called defensive locomotive system in 6OHDA-lesioned rats.
CO activity of Girk2(Wv) mutants was abnormal in cerebellar cortex, dentate nucleus, and brainstem regions (medial and lateral vestibular nuclei, prepositus, superior colliculus, lateral cuneiform nucleus, and reticular nuclei) implicated in the gaze system.
Impregnated neurons from the periaqueductal gray (PAG), posterior hypothalamic area (PH), nucleus of the tractus solitarius (NTS), and cuneiform nucleus (CfN) were examined in coronal sections.
A smaller projection to the ipsilateral LN also arises from the anterior EG, which is the only region of auditory cortex to target tegmental areas surrounding the IC, including the superior colliculus, periaqueductal gray, intercollicular tegmentum, and cuneiform nucleus.
The results obtained showed that freezing behavior induced by semicarbazide was associated with an increase in Fos expression in the dorsomedial column of the PAG (dmPAG) only, while bicuculline-induced escape was related to widespread increase in Fos labeling, notably in the periaqueductal gray, hypothalamus nuclei, amygdaloid nuclei, the laterodorsal nucleus of thalamus (LD), the cuneiform nucleus (CnF) and the locus coeruleus (LC).
We report that the afferent projections to the subparafascicular nucleus and area include the medial prefrontal, insular, and ectorhinal cortex, the subiculum, the lateral septum, the anterior amygdaloid area, the medial amygdaloid nucleus, the caudal paralaminar area of the thalamus, the lateral preoptic area, the anterior, ventromedial, and posterior hypothalamic nuclei, the dorsal premamillary nucleus, the zona incerta and Forel's fields, the periaqueductal gray, the deep layers of the superior colliculus, cortical layers of the inferior colliculus, the cuneiform nucleus, the medial paralemniscal nucleus, and the parabrachial nuclei.
The distribution of on- and off-cells in the mesopontine tegmentum overlapped and included the cholinergic PPTg and lateral dorsal tegmental nucleus identified by NADPH diaphorase staining, as well as the cuneiform nucleus and periaqueductal gray.
The highest density of immunoreactive fibers was found in the motor trigeminal nucleus, the laminar and alaminar spinal trigeminal nuclei, the facial nucleus, the marginal nucleus of the brachium conjunctivum, the locus coeruleus, the cuneiform nucleus, the dorsal motor nucleus of the vagus, the postpyramidal nucleus of the raphe, the lateral tegmental field, the Kölliker-Fuse nucleus, the inferior central nucleus, the periaqueductal gray, the nucleus of the solitary tract, and in the inferior vestibular nucleus.
Impregnated neurons from seven brain areas were examined in coronal sections: the periaqueductal gray, posterior hypothalamic area, nucleus of the tractus solitarius, rostral ventrolateral medulla, cuneiform nucleus, nucleus cuneatus, and cerebral cortex. There were significant differences between groups in the posterior hypothalamic area, periaqueductal gray, cuneiform nucleus, and nucleus of the tractus solitarius in the inner rings, outer rings, and the total number of intersections per animal.
The context-exposed group showed Fos expression in a subset of the regions activated by cat odor itself: the dorsal premammillary nucleus, ventrolateral periaqueductal grey, cuneiform nucleus and locus ceruleus.
The results obtained showed that freezing behavior induced by semicarbazide was associated with an increase in Fos expression in the laterodorsal nucleus of the thalamus (LD) and ventrolateral periaqueductal gray (vlPAG), while bicuculline-induced escape was related to widespread increase in Fos labeling, notably in the columns of the periaqueductal gray, hypothalamus nuclei, the central amygdaloid nucleus (Ce), the LD, the cuneiform nucleus (CnF) and the locus coeruleus (LC).
In contrast, in the latter group, receptors were decreased in the CA1 area, hypothalamus dorsal, frontal cortex (1 and 3), occipital cortex, cingulate cortex (1 and 2), and cuneiform nucleus.
From these studies, it has been suggested that a pathway involving the dPAG itself, dorsomedial hypothalamus and the cuneiform nucleus (CnF) would mediate responses to immediate danger and another one involving the amygdala and ventrolateral periaqueductal gray (vlPAG) would mediate cue-elicited responses.
The inclusions were located within cholinergic and other neurons in the pedunculopontine nucleus, cuneiform nucleus, and griseum centrale mesencephali and stained positively for ubiquitin, torsinA, and the nuclear envelope protein lamin A/C.
Nociceptive neurons have also been reported in the vicinity of the PPTg and cuneiform nucleus (CN). Excited (n=9), inhibited (n=10) and non-responsive neurons (n=10) were also found more dorsally within the cuneiform nucleus. Thus, this study localizes nociception-responsive neurons to the region of the largely cholinergic PPTg, as well as the noncholinergic cuneiform nucleus..
However, midazolam failed to affect cat odor-related Fos expression in a range of key defense-related sites, including the ventromedial hypothalamic nucleus, paraventricular nucleus of the hypothalamus, periaqueductal gray, and cuneiform nucleus.
Other pontomesencephalic regions outside of the dPAG demonstrating a significant increase in FLI relative to controls included the lateral and ventrolateral columns of the PAG, the cuneiform nucleus, dorsal raphe, and the microcellular tegmental nucleus.
It has been suggested that there are at least two pathways for periaqueductal gray-mediated defensive responses, one involving the hypothalamus and the cuneiform nucleus (CnF) which mediates responses to immediate danger and another one involving the amygdala and vlPAG which mediates cue-elicited responses, either learned or innate. Escape-provoking stimulation caused increased Fos expression in the ventromedial hypothalamus (VMH), dorsal premammilary nucleus (PMd) and in the cuneiform nucleus.
Following lesions of the medial paralemniscal nucleus, TIP39-immunoreactive fibers disappeared from the medial geniculate body, the periaqueductal gray, the deep layers of the superior colliculus, the external cortex of the inferior colliculus, the cuneiform nucleus, the nuclei of the lateral lemniscus, the lateral parabrachial nucleus, the locus coeruleus, the subcoeruleus area, the medial nucleus of the trapezoid body, the periolivary nuclei, and the spinal cord, suggesting that these regions receive TIP39-containing fibers from the medial paralemniscal nucleus, and unilateral lesions demonstrated that the projections are ipsilateral.
In four squirrel monkeys (Saimiri sciureus), the inferior colliculus, together with the neighboring superior colliculus, reticular formation, cuneiform nucleus and parabrachial area, were explored with microelectrodes, looking for neurons that might be involved in the discrimination between self-produced and external sounds.
Repetitive stimulation (50 Hz, 10-60 microA, for 5-20 s) applied to a mesencephalic locomotor region (MLR), which corresponded to the cuneiform nucleus, and adjacent areas, evoked locomotor movements.
Apart from a dense afferent projection from the retina- and the contralateral leaflet, there were ipsilateral projections from other structures: layer V and VI of the prefrontal cortex, the zona incerta, the magnocellular part of the subparafascicular nucleus, the dorsal raphe nucleus, the locus coeruleus, and the cuneiform nucleus.
Therefore, the present data bring support to the notion that amygdala, dorsal hippocampus, entorhinal cortex, frontal cortex, dorsal periaqueductal gray matter and cuneiform nucleus altogether play a role in the integration of aversive states generated at the level of the inferior colliculus..
In addition, most intralaminar injections resulted in retrograde cell body labeling in the substantia nigra, nucleus Darkschewitsch, interstitial nucleus of Cajal, and cuneiform nucleus.
Immunoreactive elements were mainly localized to the spinal trigeminal, cuneate, solitary, vestibular, and cochlear sensory nuclei, dorsal motor nucleus of the vagus nerve, ventral grey column, hypoglossal nucleus, dorsal and ventrolateral medullary reticular formation, pontine subventricular grey and locus coeruleus, lateral regions of the rostral pontine tegmentum, tectal plate, trochlear nucleus, dorsal and median raphe nuclei, caudal and rostral linear nuclei, cuneiform nucleus, and substantia nigra.
Significant findings included strong and selective induction of Fos in the posteroventral medial amygdaloid nucleus, the premamillary nucleus (dorsal part), ventromedial hypothalamic nucleus (dorsomedial part), dorsomedial hypothalamic nucleus, periaqueductal gray (dorsomedial, dorsolateral and ventrolateral parts) and the cuneiform nucleus.Robust Fos expression in the ventromedial hypothalamus, premamillary nucleus and periaqueductal gray confirms previous suggestions of a role for these areas in predator-induced defensive behavior.
PIA stimulation evoked bilateral muscle tone suppression and inhibited 26 of 28 LC units and 33 of 36 tonically active units located in the anatomical equivalent of the MLR (caudal half of the cuneiform nucleus and the pedunculopontine tegmental nucleus).
In the brainstem, staining was particularly prominent in the substantia nigra pars reticulata and compacta, the central gray substance, the superior colliculus, and the cuneiform nucleus, and staining was moderate in the tegmenti pedonculopontinus nucleus and the griseum pontis.
In contrast, c-fos expression within the anterior and ventromedial nuclei of the hypothalamus, dorsal periaqueductal grey, dorsal raphe, cuneiform nucleus, and locus coeruleus did not differ between AD and CD groups.
Thus, we have shown that the nucleus receives substantial inputs from the prefrontal cortex, specific domains of the rostral part of the lateral septal nucleus, rostral zona incerta, perifornical region, anterior hypothalamic nucleus, ventromedial hypothalamic nucleus, dorsal premammillary nucleus, medial regions of the intermediate and deep layers of the superior colliculus, and cuneiform nucleus.
By contrast, pain behavior was unaffected by microinjections of the cannabinoid into the other 11 areas examined (prefrontal cortex, nucleus accumbens, lateral hypothalamus, substantia nigra, cuneiform nucleus, anterior pretectal, intralaminar, parafasicular, posterior, thalamic nuclei, as well as the ventral medial, ventral lateral nuclei in the posterior thalamus)..
Active cells labeled with c-fos within the mesencephalic locomotor region (MLR) have been found in the periaqueductal gray, the cuneiform nucleus, the pedunculopontine nucleus, and the locus coeruleus.
These results may be a support to the hypothesis that the N18 component generator is related to the mechanism of presynaptic inhibition within the cuneiform nucleus..
In SUB males, c-fos expression increased within a multitude of brain areas, including cingulate cortex, lateral septum, bed nucleus of the stria terminalis, medial preoptic area, several hypothalamic nuclei, central amygdaloid nucleus, amygdalohippocampal area, dorsal periaqueductal gray, dorsal raphe, cuneiform nucleus, and locus coeruleus.
Supramedullary structures including the ventral medial prefrontal cortex (MPFC) and the midbrain cuneiform nucleus (CnF) project directly and indirectly to premotor sympatho-excitatory neurons of the rostral ventrolateral medulla (RVLM) that are critically involved in the generation of sympathetic vasomotor tone. cuneiform nucleus stimulation induces the expression of mRNA for the immediate early genes c-fos and NGFI-A in mid-brain, pontine and hypothalamic structures.
Forebrain neuronal connections associated with the cardiovascular response to unilateral, low-intensity, electrical stimulation of the mesencephalic cuneiform nucleus were examined in the halothane-anesthetized and paralysed rat by in situ hybridization histochemistry using specific 35S-labelled oligonucleotides for detection of c-fos and nerve growth factor inducible-A gene (NGFI-A) messenger RNAs. Stimulation of the cuneiform nucleus led to increases in mean arterial pressure and heart rate, whereas no cardiovascular response was observed in animals stimulated in the inferior colliculus or in sham-operated animals [ see concurrent mid- and hindbrain study [ Lam W. cuneiform nucleus stimulation was associated with increased c-fos and NGFI-A messenger RNA levels bilaterally in the ventromedial, dorsomedial and lateroanterior hypothalamic nuclei, lateral and anterior hypothalamic areas, and ipsilaterally in the medial amygdaloid nucleus, at levels significantly greater than those in inferior colliculus-stimulated, sham-operated and naive, unoperated animals. These results are consistent with the existence of direct and indirect projections between the cuneiform nucleus and the aforementioned activated areas, the functions of which may include the control of reproduction and metabolism, as well as cardiovascular regulation. The existence of structures that are known to receive afferent projections from the cuneiform nucleus, but that were not activated, may be explained by synaptic depolarization not reaching the threshold for immediate early gene expression or by a net inhibitory effect on innervated neurons. Characterization of these activated forebrain regions using other compatible labelling techniques should further elucidate the mechanisms by which these central nervous system structures are integrated in the response to stimulation of the cuneiform nucleus..
Stimulation of the midbrain cuneiform nucleus has previously been shown to produce increases in arterial blood pressure and lumbar sympathetic nerve activity. While this sympathoexcitatory effect is, in part, due to excitation of premotor sympathoexcitatory neurons in the rostral ventrolateral medulla, the specific spinal neurotransmitter systems recruited by cuneiform nucleus stimulation remains to be elucidated. In this study, mean arterial pressure, resting and cuneiform nucleus stimulation-evoked lumbar sympathetic nerve activity were analysed following intrathecal injections of an excitatory amino acid antagonist (kynurenic acid), alpha1-adrenoceptor antagonist (prazosin) and a serotonin receptor antagonist (methiothepin) in anesthetized, paralysed male Sprague-Dawley rats. Intermittent electrical stimulation of the cuneiform nucleus produced a bimodal sympathoexcitatory response, of which the short latency peak was significantly attenuated (43% reduction) by intrathecal kynurenate whereas the long latency peak was reduced by intrathecal prazosin (decrease of 21%) and methiothepin (38% attenuation). These results are consistent with the significant roles of excitatory amino acid, alpha1-adrenergic and serotonin receptors in modulating the activity of sympathetic vasomotor preganglionic neurons supplying the lumbar sympathetic nerve trunk, and suggest the existence of at least three neuronal groups and/or pathways associated with the sympathoexcitatory response to cuneiform nucleus stimulation..
Connections to the dorsal part of the periaqueductal grey, the cuneiform nucleus and the parabrachial region are important in the context of vocal control, whereas projections to the medial portion of the contralateral facial nucleus may interfere with the control of pinna movement.
A low density was found in the superior and inferior colliculi, the interpeduncular nucleus, the nucleus sagulum, the superior central nucleus, the cuneiform nucleus, the accessory dorsal tegmental nucleus, the nucleus of the solitary tract, the dorsal motor nucleus of the vagus, and the paralemniscal, magnocellular, gigantocellular, and lateral tegmental fields.
These were in or near the mesencephalic reticular nucleus, brachium of the inferior colliculus, cuneiform nucleus, superior colliculus, central gray, and substantia nigra.
TRH receptors were widely distributed in multiple brain areas, including in the VTF and the cuneiform nucleus (CnF) which terminates in the VTF.
Descending fibers from the caudal GP course in the cerebral peduncle and project to posterior thalamic nuclei (the subparafascicular and suprageniculate nuclei, medial division of the medial geniculate nucleus, and posterior intralaminar nucleus/peripeduncular area) and to extensive brainstem territories, including the pars lateralis of the substantia nigra, lateral terminal nucleus of the accessory optic system, nucleus of the brachium of the inferior colliculus, nucleus sagulum, external cortical nucleus of the inferior colliculus, cuneiform nucleus, and periaqueductal gray.
Heavily stained neuronal nuclei, prevailing on the brain side ipsilateral to the injection of picrotoxin, were localized within a narrow strip of tissue which stretched from the ventrolateral periaqueductal gray (including the dorsal raphe), the cuneiform nucleus, through the region of the dorsal tegmental bundle to the pedunculopontine nucleus.
Increased labelling with EX was found in both colliculi, the periaqueductal gray matter, the parabrachial complex and the cuneiform nucleus ('mesencephalic locomotor region').
Less dense terminals were also seen in the nucleus of the brachium of the inferior colliculus, the cuneiform nucleus, the medial part of the paralemniscal tegmental field, and the dorsolateral division of the pontine nuclei on the ipsilateral side.
Functional neuronal connections associated with the cardiovascular response to unilateral low-intensity electrical stimulation of the mesencephalic cuneiform nucleus were examined in the halothane-anaesthetized and paralysed rat by in situ hybridization histochemistry using specific 35S-labelled oligonucleotides for detection of nerve growth factor inducible-A gene (NGFI-A) and c-fos messenger RNAs. Stimulation of the cuneiform nucleus increased mean arterial pressure and heart rate by 20 +/- 0.5 mmHg and 35 +/- 3 b.p.m., respectively, while no significant cardiovascular response was observed in animals stimulated in the inferior colliculus or in sham-operated animals. cuneiform nucleus stimulation produced increased NGFI-A and c-fos messenger RNA levels in the Kölliker-Fuse and parabrachial nuclei ipsilaterally, and the cuneiform nucleus, dorsal periaqueductal gray and caudal ventrolateral medulla bilaterally at levels significantly greater than those in inferior colliculus-stimulated, sham-operated and naive, unoperated animals. These results are consistent with previous neuroanatomical tract-tracing studies of afferent and efferent pathways from the cuneiform nucleus and indicate that these midbrain and hindbrain structures may be involved in the pressor and tachycardic responses associated with stimulation of the cuneiform nucleus. Characterization of these activated neuronal structures using other compatible labelling techniques should further elucidate the mechanisms by which these central nervous system structures are integrated in the cardiovascular responses to stimulation of the cuneiform nucleus..
Combined physiological and neuroanatomical studies suggest that a specific forebrain-brain stem network, composed of connections between the central nucleus of the amygdala, the paraventricular nucleus of the hypothalamus, the mesencephalic cuneiform nucleus, the parabrachial nucleus and the dorsal motor nucleus of the vagus nerve, may be important for integrating behavioural and physiological responses.
The cuneiform nucleus and the pedunculopontine tegmental nucleus have both been suggested as possible sites for the mesencephalic locomotor region (MLR), an area from which controlled stepping on a treadmill can be elicited following electrical or chemical stimulation in a decerebrate animal. Excitotoxic lesions of the cuneiform nucleus have not previously been investigated. Rats received either bilateral ibotenate or sham lesions of the cuneiform nucleus combined with bilateral implantation of guide cannulae aimed at the nucleus accumbens. These results suggest that, like the pedunculopontine tegmental nucleus, the cuneiform nucleus is not involved in the direct mediation of spontaneous or accumbens-induced locomotion, and thus is very unlikely to be the anatomical substrate of the MLR. The role of the cuneiform nucleus in other types of behavioural control is discussed..
Kindled seizure generalization also increased c-fos-like immunoreactivity (FLI) in the inferior collicular cortex, cuneiform nucleus, dorsal lateral nucleus of the lateral lemniscus, peripeduncular nucleus, caudal central gray, dentate gyrus of the hippocampus, rhinal fissure area of the perirhinal cortex and the frontal cortex. Conversely, procaine microinjection into the area of the cuneiform nucleus/pedunculopontine tegmental nucleus prevented the wild running seizure but did not block the generalized seizure activity.
Fourteen SHT axons (40%) ended in the ipsilateral midbrain mainly in the superior colliculus, cuneiform nucleus or nucleus brachium inferior colliculus.
Terminations were observed in the solitary nucleus, the dorsomedial medullary reticular formation, the entire rostrocaudal extent of the ventrolateral medulla, the locus coeruleus, the subcoerulear region and the Kölliker-Fuse nucleus, the lateral and medial portions of the parabrachial nucleus, the cuneiform nucleus, the ventrolateral and lateral portions of the periaqueductal gray, and the intercollicular nucleus.
At a general level the dorsal midbrain anticonvulsant zone shares its major output projections and efferent targets with at least one of its near neighbours, including the superior colliculus, periaqueductal gray, the cuneiform nucleus and pedunculopontine nucleus.
Distally, clusters of labeled cells were found ipsilaterally in the piriform and entorhinal cortices, in several amygdaloid nuclei, in the bed nucleus of the stria terminalis, in the septo-hypothalamic nucleus, in the paraventricular, anterior and dorsomedial hypothalamic nuclei, the the paraventricular thalamic nucleus, in the dorsal periaqueductal gray extending to the cuneiform nucleus, and bilaterally in the supramammillary decussation and the locus coeruleus.
By contrast, the labeling was weak or absent in the other PB subnuclei and the outer adjacent regions; in particular, no, or very little, labeling was found in the cuneiform nucleus.
Activation of the cuneiform nucleus (CNF) of the midbrain produces elevation of arterial blood pressure.
Dense serotoninergic innervation were also found to receive the following brainstem structures: lateral hypothalamic area; dorsal part of the suprachiasmatic nucleus; arcuate nucleus; median eminence; habenular nuclei; centromedian thalamic nucleus; ventral tegmental area; medial part of the substantia nigra; interpeduncular nucleus; locus coeruleus; cuneiform nucleus; motor nucleus of the trigeminal nerve; facial nucleus; parabrachial nucleus; prepositus hypoglossi nucleus; medial subnucleus of the nucleus of the solitary tract; hypoglossal nucleus; dorsal motor nucleus of the vagus.
The effects of short trains of electrical stimuli applied within the cuneiform nucleus and the subcuneiform region were examined on transmission from group I and group II muscle afferents to first-order spinal neurons. Field potentials evoked from group II muscle afferents in the dorsal horn of the midlumbar and sacral segments and in the intermediate zone of the midlumbar segments were reduced when the test stimuli applied to peripheral nerves were preceded by conditioning stimulation of the cuneiform nucleus or the subcuneiform region. Conditioning stimulation of the cuneiform nucleus depressed group II field potentials nearly as effectively as conditioning stimulation of the coerulear or raphe nuclei. We also propose that the selective depression of transmission from group II afferents at long intervals is mediated at least partly by monoaminergic pathways, in view of the similarity of the effects of conditioning stimulation of the cuneiform nucleus and of the brainstem monoaminergic nuclei and by directly applied monoamines (Bras et al.
In pons and midbrain, Fos-like immunoreactivity was observed in the lateral parabrachial and Kölliker-Fuse nuclei, the inferior colliculus, the cuneiform nucleus, and in the vicinity of the Edinger-Westphal nucleus, but no catecholaminergic or serotoninergic colocalization was observed in these regions.
The densest clusters of immunoreactive perikarya were found in the inferior and superior colliculi, the inferior olive, the periaqueductal gray, the central tegmental field and the substantia nigra, whereas the central linear nucleus, the locus coeruleus, the nucleus incertus, the dorsal and ventral nuclei of the lateral lemniscus, the cuneiform nucleus, the pontine gray, the Kölliker-Fuse nucleus, the dorsal motor nucleus of the vagus and the medial nucleus of the solitary tract had the lowest density. A moderate density of calbindin-immunoreactive fibers was found in the retrorubral nucleus, the central linear nucleus, the locus coeruleus, the nucleus sagulum, the dorsal nucleus of the raphe, the cuneiform nucleus, the ventral and dorsal nuclei of the lateral lemniscus, the medial nucleus of the solitary tract, the dorsal motor nucleus of the vagus, and the cuneate nucleus.
Retrogradely labeled neurons were also consistently found in the nucleus of the solitary tract, in the vicinity of the lateral reticular nucleus, nucleus paragigantocellularis, parabrachial nucleus, Kölliker-Fuse nucleus, cuneiform nucleus, raphe nucleus and zona incerta.
The periaqueductal gray, brachium of the inferior colliculus, nucleus of the brachium of the inferior colliculus, locus coeruleus, nucleus incertus, Kölliker-Fuse nucleus, facial nucleus, medial nucleus of the solitary tract and the area postrema contained a moderate density of immunoreactive fibres, whereas the pericentral nucleus of the inferior colliculus, nucleus sagulum, cuneiform nucleus, dorsal nucleus of the raphe, superior central nucleus, central, lateral and paralemniscal tegmental fields, ventral nucleus of the lateral lemniscus, dorsal tegmental nucleus, postpyramidal nucleus of the raphe, nucleus ambiguus, accessory dorsal tegmental nucleus, dorsal motor nucleus of the vagus and the inferior olive had the lowest density of immunoreactive fibres..
However, the neurons in the pars compacta of the substantia nigra, paranigral nucleus, parabrachial pigmental nucleus, tegmental pedunculopontine nucleus, supratrocheal nucleus, cuneiform nucleus, subcuneiform nucleus and lemniscus medialis, which were positive in other diseases and in non-neurological controls, were not stained by these antibodies in PD brains.
By contrast, the interpeduncular nucleus, magnocellular part of the red nucleus, central tegmental field, cuneiform nucleus, dorsal tegmental nucleus, nucleus sagulum and the medial and inferior vestibular nuclei had the lowest density, whereas a moderate density of immunoreactive cell bodies was found in the superior colliculus, medial division of the dorsal nucleus of the raphe, nucleus incertus, locus coeruleus and in the Kölliker-Fuse area. A moderate density of immunoreactive fibers was found in the dorsal motor nucleus of the vagus and in the postpyramidal nucleus of the raphe and a low density in the cuneiform nucleus, Kölliker-Fuse area, nucleus sagulum, inferior and superior central nuclei, lateral reticular nucleus and in the lateral and magnocellular tegmental fields..
The supramammillary nucleus also receives a few (but distinct) fibers from the anterior and lateral hypothalamic nuclei, the ventral premammillary nucleus, the interpeduncular nucleus, the cuneiform nucleus, the dorsal raphe nucleus, the incertus nucleus, and the C3 region including the prepositus hypoglossi nucleus.
Two hours after the test, labeling was found mainly in the piriform and entorhinal cortices, amygdala, midline thalamic nuclei, several medial hypothalamic nuclei, periaqueductal gray matter, superior and inferior colliculus, cuneiform nucleus, dorsal raphe nucleus and locus coeruleus.
In the 4-Hz-treated group, significant increases in Fos labeling were also observed in the cuneiform nucleus, dorsal and laterodorsal subdivisions of the periaqueductal gray, habenular nucleus, arcuate hypothalamic nucleus, and the lateroventral and lateral hypothalamic nuclei as compared to non-stimulated controls.
The nucleus ruber, cuneiform nucleus, preolivary nucleus, retrorubral nucleus, paracentral division of the tegmental reticular nucleus, central and lateral tegmental fields, and the pericentral division of the dorsal tegmental nucleus had the lowest density of immunoreactive cell bodies. Moreover, a high or moderate density of parvalbumin immunoreactive processes was visualized in the nucleus ruber, substantia nigra, superior and inferior colliculi, periaqueductal gray, nucleus sagulum, cuneiform nucleus, Kölliker-Fuse nucleus, nucleus of the trapezoid body, vestibular nuclei, dorsal motor nucleus of the vagus, and in the lateral reticular nucleus.
The aim of the present study was to explore the neuroanatomic network that underlies the cardiovascular responses of reticular formation origin in the region of the cuneiform nucleus (CNF). On the basis of the present physiological and neuroanatomical study, a brain circuit has been proposed in which the cuneiform nucleus has a central position.
It is suggested that some of the disynaptic tegmental EPSPs in SPL and BCC motoneurones can be mediated via a tegmento-reticulospinal pathway which originates in the cuneiform nucleus..
However, lesions of the following structures did not modify DNIC: Periaqueductal grey (PAG), cuneiform nucleus, Parabrachial area, locus coeruleus/subcoeruleus, rostral ventromedial medulla (RVM) including Raphe Magnus, Gigantocellularis and Paragigantocellularis nuclei.
biceps were evoked from regions rostrally and ventrally of LC, the caudal pontine reticular nucleus, the cuneiform nucleus and from the ventral parts of the colliculus inferior.
Cells of origin of these projections were localized in the caudal 2/3 of the GP, and their major target sites included the peripeduncular region, nucleus of the brachium of the inferior colliculus, para-lateral lemniscal zone, nucleus sagulum, external and pericentral nuclei of the inferior colliculus, and cuneiform nucleus.
When PHA-L was injected into the magnocellular and/or parvicellular division of the SPF (SPFm and/or SPFp), presumed terminal labeling was seen, bilaterally with an ipsilateral dominance, in the mesencephalic and pontine central gray matter, peripheral shell regions of the inferior colliculus, cuneiform nucleus, and superior olivary complex (mainly in the superior paraolivary nucleus, and additionally in the nuclei of the trapezoid body).
Finally, few immunoreactive fibers were visualized in the interpeduncular nucleus, cuneiform nucleus, locus coeruleus, nucleus incertus, superior and inferior central nuclei, nucleus sagulum, ventral nucleus of the lateral lemniscus, nucleus praepositus hypoglosii, medial vestibular nucleus, Kölliker-Fuse area, nucleus ambiguous, retrofacial nucleus, postpyramidal nucleus of the raphe, nucleus of the solitary tract, dorsal motor nucleus of the vagus, lateral reticular nucleus and laminar and alaminar spinal trigeminal nuclei..
A few labelled neurons were observed in the periaqueductal gray, the cuneiform nucleus and superior colliculus of the mesencephalon as well as the alamina spinal trigeminal nucleus.
The electrical stimulation also identified a number of regions that would support electrically dependent seizure behaviors: the cuneiform nucleus, the ventrolateral inferior colliculus, portions of the dorsal central gray, and the peripeduncular nucleus.
Type I cells were observed in the following areas: the piriform cortex, field CA1 of Ammon's horn, subiculum, vertical, and horizontal limbs of the diagonal band of Broca, intermediate part of the lateral septal nucleus, bed nucleus of the stria terminalis, medial preoptic area, lateral hypothalamus, caudal part of the caudate putamen, medial, cortical, and central amygdaloid nuclei, ventral tegmental area, deep mesencephalic nucleus, cuneiform nucleus, dorsal raphe nucleus, laterodorsal tegmental nucleus, parabrachial nucleus, and oral part of the pontine reticular nucleus.
Since the ipsilaterally projecting laminae V-VII interneurones with such an input might be involved in locomotion, it is proposed that this is also the case for the contralaterally projecting lamina VIII midlumbar interneurones, especially those excited by stimuli applied in the cuneiform nucleus (mesencephalic locomotor region)..
These areas include zona incerta, nucleus of the posterior commissure, anterior and posterior pretectal nuclei, nucleus of the optic tract, superior colliculus, cuneiform nucleus, subcuneiform area, substantia nigra pars reticulata and pars lateralis, periparabigeminal area, external nucleus of the inferior colliculus, the area ventral to the external nucleus of the inferior colliculus, mesencephalic reticular formation, dorsal and ventral nuclei of the lateral lemniscus, and the perihypoglossal nucleus.
The relative density of labelled cells in mesencephalic areas was much lower than that found in cortex and hypothalamus, although D[ 3H]aspartate labelled a moderate number of perikarya in the inferior colliculus and cuneiform nucleus.
In pontine regions and the cuneiform nucleus adjacent to these three vocal areas, thresholds for eliciting vocalizations were also low, but the vocalizations showed temporal and/or spectral distortions and were often accompanied or followed by arousal of the animal. Bursts of multiple vocalizations were induced at locations ventral to the rostral parts of the cuneiform nucleus.
The greatest number of double-labeled glutamate-like immunoreactive neurons were observed in the zona incerta, spinal trigeminal nucleus, cuneiform nucleus, cingulate cortex, cerebellar interpositus nucleus, deep mesencephalic nucleus and the PAG itself.
In the cuneiform nucleus, a lesser and a denser binding site were observed in the medial and lateral halves respectively.
Neurons located in the area of the cuneiform nucleus dorsal to the pedunculopontine nucleus were found to be related preferentially to cyclic (bursting) neurographic activity, while neurons in the area of the pedunculopontine were found to be related preferentially to the onset ("on") or termination ("off") of cycling episodes.
These procedures were electrical stimulation within the cuneiform nucleus (the 'mesencephalic locomotor region') in anaesthetized preparations and systemic administration of 3,4-dihydroxyphenylalanine (DOPA) in decerebrate, spinalized, unanaesthetized preparations. Stimuli applied in the cuneiform nucleus evoked excitatory postsynaptic potentials (EPSPs) in a high proportion of these interneurones. The neurones which appeared to be monosynaptically excited from the cortico- and rubrospinal tracts tended to be located dorsal to the neurones which were activated from the cuneiform nucleus. By showing that both stimulation in the cuneiform nucleus and the administration of DOPA influence activity of L4 interneurones which are excited by group II afferents and which project to motor nuclei, the results of this study support the hypothesis that these neurones are in some way involved in locomotion. However, the opposing effects of DOPA administration and of stimulation in the cuneiform nucleus make the interpretation of their role in locomotion rather difficult before it is known to what extent they are active throughout the step cycle..
These cholinergic neurons constituted over 20% of those retrogradely labelled in the dorsolateral mesopontine tegmentum; the balance consisted of noncholinergic neurons of the central tegmental field, retrorubral field, and cuneiform nucleus.
Influence of serotonin- and GABA-ergic systems on cataleptic responses to electrical stimulation of the medial parabrachial nucleus, cuneiform nucleus, median and magnus raphe nuclei, was investigated in chronic experiments on rats.
To investigate the role of the projection from superior colliculus to the cuneiform nucleus in mediating collicular responses, the cuneiform area (including the cuneiform nucleus and immediately adjacent structures such as caudal central grey) was stimulated in rats with microinjections of glutamate (50 mM, 200 nl, 10 nmole) and the animals' head and body movements observed. Involvement with such responses would be consistent with an apparent lack of topography in the tectocuneiform projection, and the connections of the cuneiform nucleus with parts of the brain concerned with nociception (see previous paper).
We therefore carried out two studies to investigate in rats the part of the ipsilateral projection that terminates in an area ventral to the inferior colliculus, referred to as the cuneiform nucleus. Injections of WGA-HRP into the superior colliculus gave terminal label in the cuneiform nucleus and also in surrounding structures which included central grey, the midbrain tegmentum bordering the parabigeminal nucleus, and the external nucleus of the inferior colliculus. Label in the cuneiform nucleus was heaviest after injections into the medial deep layers. A similar distribution of labelled cells was seen after injections into the structures next to the cuneiform nucleus that also receive a tectal projection. The projection from the superior colliculus to the cuneiform nucleus and immediately adjacent areas may therefore be also functionally distinct, mediating a particular kind of tectally-elicited response.
(1) Injection of tracer into the spinal enlargements resulted in dense terminal labeling in the parabrachial nucleus (PBN) and the periaqueductal gray matter (PAG); moderate termination was observed in the intercollicular nucleus (Inc), the intermediate and deep gray layers of the superior colliculus (SGI, SGP), the posterior pretectal nucleus (PTP), and the nucleus of Darkschewitsch (D); and scattered terminal fibers were seen in the cuneiform nucleus (CNF) and the pars compacta of the anterior pretectal nucleus (PTAc).
Besides the CRFI cells in the paraventricular hypothalamic nucleus that project to the median eminence, CRFI cells were demonstrated in many brain regions, including the olfactory bulb, cerebral cortex, septal nuclei, hippocampus, amygdala, thalamic nuclei, medial hypothalamic nuclei, lateral hypothalamic area, perifornical area, central gray, cuneiform nucleus, inferior colliculus, raphe nuclei, mesencephalic reticular formation, laterodorsal tegmental nucleus, locus coeruleus, parabrachial nuclei, mesencephalic tract of the trigeminal nerve, pontine reticular formation, lateral superior olive, vestibular nuclei, prepositus hypoglossal nucleus, nucleus of the solitary tract, dorsal motor nucleus of the vagus, lateral reticular nucleus, nucleus of the spinal tract of the trigeminal nerve, external cuneate nucleus, inferior olive, and medullary reticular formation.
Furthermore, isolated retrogradely labeled cells were present in the central nucleus of the raphe, in the cuneiform nucleus, and in the periaqueductal gray.
Based on both retrograde and anterograde transport methods, our results suggest that the PPA: receives its main afferent projections from the insulotemporal cortex, basal ganglia, ventromedial and posterior hypothalamic nuclei, zona incerta, inferior colliculus, intermediate and deep layers of the superior colliculus, central gray, cuneiform nucleus, laterodorsal tegmental nucleus, and dorsal nucleus of the lateral lemniscus and, projects essentially to the basal ganglia, ventromedial hypothalamic nucleus, central gray, cuneiform and pedunculopontine nuclei, deep layers of the superior colliculus, inferior colliculus, and dorsal and ventral nuclei of the lateral lemniscus.
Bilateral stimulation of electrodes aimed at the cuneiform nucleus produced significant inhibition of the startle response produced by presentation of an 8-kHz, 110-dB tone. Stimulation of electrodes aimed at the deep mesencephalic nucleus also reduced the magnitude of the startle response, but the effect was less than that following stimulation sites near the cuneiform nucleus. Histological reconstruction of the electrode tip locations revealed a significant negative correlation between the maximum magnitude reduction of the acoustic startle response following an electrical prepulse stimulus and the distance from the cuneiform nucleus. Histological examination also indicated that some electrodes aimed at the cuneiform nucleus were located in or near the inferior colliculus or parabrachial nucleus, all of which are thought to be part of an inhibitory circuit parallel to the acoustic startle reflex arc.
The cuneiform nucleus extends from the supraoptic nucleus to the ependymal lining of the third ventricle separating the suprachiasmatic nucleus from the retrochiasmatic nucleus.
Caudally, projecting fibres leave the main bundle to innervate the cuneiform nucleus, and parts of the pontomedullary reticular formation.
At midbrain, pontine and medullary levels, additional labelled regions were: the substantia nigra, cuneiform nucleus, parabigeminal nucleus, raphe magnus, and reticular areas.
DYN B cell bodies were present in nonpyramidal cells of neo- and allocortices, medium-sized cells of the caudate-putamen, nucleus accumbens, lateral part of the central nucleus of the amygdala, bed nucleus of the stria terminalis, preoptic area, and in sectors of nearly every hypothalamic nucleus and area, medial pretectal area, and nucleus of the optic tract, periaqueductal gray, raphe nuclei, cuneiform nucleus, sagulum, retrorubral nucleus, peripeduncular nucleus, lateral terminal nucleus, pedunculopontine nucleus, mesencephalic trigeminal nucleus, parabigeminal nucleus, dorsal nucleus of the lateral lemniscus, lateral superior olivary nucleus, superior paraolivary nucleus, medial superior olivary nucleus, ventral nucleus of the trapezoid body, lateral dorsal tegmental nucleus, accessory trigeminal nucleus, solitary nucleus, nucleus ambiguus, paratrigeminal nucleus, area postrema, lateral reticular nucleus, and ventrolateral region of the reticular formation.
Lamina I spinomesencephalic neurons were antidromically activated from the region that included the cuneiform nucleus and lateral periaqueductal gray at the intercollicular level.
These tegmental neurons were distributed not only in the pedunculopontine tegmental nucleus (PPTN) (26 cells), but also in the cuneiform nucleus (CNF) (13 cells), the central gray substance (CG) (four cells), the parabrachial nucleus (three cells), and the tegmentum between the inferior colliculus and the CG (two cells).
Smaller numbers of WGA-HRP labeled cells appeared in bed nucleus of stria terminalis, diagonal band of Broca, cuneiform nucleus, superior vestibular nucleus, pontine periventricular gray, and some hypothalamic and reticular areas.
Among extrahypothalamic regions, the substantia nigra, dorsal tegmental nucleus, cuneiform nucleus, dorsal parabrachial nucleus, spinal tract trigeminal nerve, interior olive, solitary nucleus, and layers I and II of the spinal cord contained 7B2-immunoreactive material.
The areas which had only efferent connections from MP were accumbens, caudate putamen, ventral pallidum, substantia innominata, lateral habenular nucleus, paratenial thalamic nucleus, paraventricular thalamic nucleus, mediodorsal thalamic nucleus, reuniens thalamic nucleus, median eminence, medial mammillary nucleus, subthalamic nucleus, pars compacta of substantia nigra, oculomotor nucleus, red nucleus, laterodorsal tegmental nucleus, reticular tegmental nucleus, cuneiform nucleus, nucleus locus coeruleus, and dorsal motor nucleus of vagus among which substantia innominata and median eminence were previously reported. Previously reported afferent connections from dorsal tegmental nucleus, cuneiform nucleus, and nucleus locus ceruleus were not detected in this study.(ABSTRACT TRUNCATED AT 400 WORDS).
The conclusion is made that the cuneiform nucleus is rather a nonspecific than auditory centre.
Dense BNST projections could be observed to the substantia nigra pars compacta, the ventral tegmental area, the nucleus of the posterior commissure, the PAG (except its dorsolateral part), the cuneiform nucleus, the nucleus raphe dorsalis, the locus coeruleus, the nucleus subcoeruleus, the medial and lateral parabrachial nuclei, the lateral tegmental field of caudal pons and medulla and the nucleus raphe magnus and adjoining medial reticular formation.
This area included the lateral part of the cuneiform nucleus and anterior as well as posterior portions of the pedunculopontine nucleus.
These neurons were distributed not only in the pedunculopontine tegmental nucleus (27 cells), but also in the cuneiform nucleus (5 cells) and the parabrachial nucleus (2 cells).
The injection sites were confined to the cuneiform nucleus (stereotaxic coordinates P2.0, L4.0, H-1.0). Projections to the contralateral cuneiform nucleus were also consistently observed.
In addition, there was a sparse projection to the cuneiform nucleus and the anterior pretectal nucleus.
More moderate projections go to the medial division of the periaqueductal gray (PAGm), the cuneiform nucleus (CF), the mesencephalic reticular formation (MRF), lateral part of the deep layer of the superior colliculus (SP) and magnocellular medial geniculate nucleus (GMmc), while scattered spinal fibers are present in the dorsal part of the periaqueductal gray (PAGd), the external inferior collicular nucleus (IX), the intermediate layer of the superior colliculus (SI), the lateral part of the red nucleus (NR) and in the Edinger-Westphal portion of the oculomotor nucleus (3).
More scattered DCN fibers are present in the cuneiform nucleus (CF), the lateral part of the periaqueductal gray (PAG1), the red nucleus (NR), the nucleus of the brachium of the inferior colliculus (B), the mesencephalic reticular formation (MRF) and the intermediate and deep layers of the superior colliculus (SI, SP).
In response to clicks or pure tones, midlatency potentials were recorded from the level of the cuneiform nucleus (14-15 ms latencies) forward through the medial tegmentum to the level of the intralaminar thalamic nuclei centralis lateralis (CL) and center median (CM) (17-19 ms latencies). Taken together these data suggest that the midlatency vertex potential, wave "A', reflects a generator system which projects from cuneiform nucleus, through the medial tegmentum to the medial thalamus, particularly to CL and CM.
Locomotion on a treadmill was elicited at low current strengths (20-50 muA) from an area around the cuneiform nucleus in the posterior mesencephalon.
Labeling was more scattered in the cuneiform nucleus, the mesencephalic reticular formation, the superior colliculus and in the magnocellular part of the medial geniculate body..
Neurons in the mesencephalic trigeminal root, cuneiform nucleus, nucleus tegmenti pedunculopontinus (NTPP), dorsal locus coeruleus and lateral central gray were labeled from Probst's tract injections.
In addition, some scattered neurons were observed in the central grey matter, the mesencephalic reticular formation, the central superior and dorsal raphe nuclei, the cuneiform nucleus reticularis gigantocellularis, the nucleus praepositus hypoglossi and the oculomotor nuclei.
More caudally, fibers from the central nucleus travel in the lateral tegmental reticular fields and contribute collaterals to the raphe nuclei, the cuneiform nucleus, and the central gray substance.
Similar abrupt losses of lordosis followed bilateral lesions of either a) the area between CG and the cuneiform nucleus of the mesencephalic reticular formation (NCf); or b) the ventrolateral quadrant of the NCf.
The other labelled structures were the prepositus hypoglossi complex (PH), the ventral nucleus of the lateral geniculate body (LGV), the locus coeruleus, the cuneiform nucleus, the periaqueductal gray and the dorsomedial hypothalamic area.
The data suggest that other connections between the superior colliculus and the facial nucleus may occur in the cuneiform nucleus of the midbrain, the region around the oculomotor complex, and the reticular formation dorsal to the superior olive..
Moderate numbers of fibers were seen in the paraventricular and arcuate nuclei, the amygdala, the region of the tractus diagonalis, the mammillary body, the central gray, the cuneiform nucleus, and the nucleus of the solitary tract.
Other ipsilateral targets of the deep tectal layers are the cuneiform nucleus and the external nucleus of the inferior colliculus.
The ascending projections of the cuneiform nucleus in the cat were traced by autoradiography in the transverse and sagittal planes following stereotaxically placed injections of (3)H-leucine.
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