Nucleus Pretectalis

Using histochemical determination of activity of the mitochondrial oxidative enzyme cytochrome oxidase (CO) in brain structures, metabolic activity both in turtles and in lizards has been shown to be higher in centers of the tectofugal channel (the tectal stratum griseum centrale, SGC; Nucleus pretectalis ventralis, Ptv; thalamic nucleus rotundus, Rot; telencephalic visual area of the anterior dorsal ventricular ridge, Advr) than in the thalamofugal channel centers (the thalamic nucleus geniculatus lateralis pars dorsalis, GLd; cortex dorsolateralis, Cxdl; and pallial thickening, Path) of the visual system.  

Among the target nuclei of tectal efferents, tracer injections to the following four structures labeled periventricular neurons: the area pretectalis pars dorsalis (APd), Nucleus pretectalis superficialis pars magnocellularis (PSm), nucleus ventrolateralis of torus semicircularis (TS), and nucleus isthmi (NI).  

The maximal CB(1) receptor density value (using [ (3)H]CP55,940 as radioligand) was found in the molecular layer of the cerebellum (Mol), and high binding values were observed in the nucleus taeniae amygdalae (TnA), nucleus preopticus medialis, and Nucleus pretectalis.  

Additional subtelencephalic cell groups showing prominent labeling included the thalamic reticular nucleus and ventral lateral geniculate nucleus of the diencephalon, the Nucleus pretectalis, subpretectalis and spiriformis lateralis of the pretectum, and the magnocellular isthmic nucleus of the optic lobe.  

Similarly, in the diencephalon and midbrain, prominent LAMP labeling was observed in such limbic areas as the dorsomedial thalamus, the hypothalamus, the ventral tegmental area, and the central midbrain gray, as well as in a few nonlimbic areas such as nucleus rotundus, the shell of the Nucleus pretectalis, the superficial tectum, and the parvocellular isthmic nucleus.  

Retinofugal terminals were located in 8 brain nuclei, the suprachiasmatic nucleus, Nucleus pretectalis superficialis, nucleus dorsolateralis thalami, area pretectalis pars dorsalis (APd), area pretectalis pars ventralis (APv), nucleus of the posterior commissure (NPC), accessory optic nucleus, and the tectum opticum.  

The Nucleus pretectalis (PT) of birds is an ovoid-shaped visuomotor cell group of the pretectum that receives tectal input and projects back to the optic tectum.  

We analyzed the connections and the immunocytochemical pattern of the subpretectalis in pigeons and show that it receives afferents from some tectal celltypes and from the Nucleus pretectalis.  

Results from these experiments demonstrate that dopaminergic neurons in the suprachiasmatic and juxtacommissural nuclei (in Rana) or in the Nucleus pretectalis (in Pleurodeles), together with noradrenergic cells of the locus coeruleus, are the sources of CA input to the amphibian mesencephalic tectum.  

The Nucleus pretectalis (NP) is a prominent nucleus in the percomorph pretectum and has been shown to project to the nucleus isthmi in the filefish by an HRP tract-tracing method [ Ito et al., 1981], but a homologous nucleus to the NP is apparently lacking in ostariophysans. The present study examined fiber connections of the nucleus isthmi in an ostariophysan teleost, the carp (Cyprinidae, Cyprinus carpio), to identify a nucleus homologous to the percomorph Nucleus pretectalis. Labeled terminals were seen in the ipsilateral Nucleus pretectalis superficialis pars parvocellularis (PSp), optic tectum, and bilateral nucleus ruber. The Nucleus pretectalis homologue is apparently absent in the carp.  

Four pretectal nuclei of the chick brain, namely, the Nucleus pretectalis, the nucleus spiriformis lateralis, the nucleus spiriformis medialis, and the nucleus lentiformis mesencephali, were included in the study, and they all showed AMPA-positive neurons.  

NPY mRNA was widely distributed in the broiler brain, and highly expressed in the hippocampus, nucleus commissurae pallii, infundibular hypothalamic nucleus, Nucleus pretectalis pars ventralis and neurons around the nucleus rotundus.  

Two ascending gamma-aminobutyric acid (GABA)ergic pathways to thalamic visual centers were revealed: a weak projection from the retinorecipient nucleus lentiformis mesencephali to the ipsilateral nucleus geniculatus lateralis pars dorsalis and a considerably stronger projection from the nonretinorecipient Nucleus pretectalis ventralis to the nucleus rotundus.  

These include projections from the Nucleus pretectalis superficialis pars magnocellularis, a nucleus lacking in percomorph teleosts, and projections from the secondary gustatory nucleus.  

We have made some specifications about the location and nomenclature of the branches belonging to the optic tracts and two nuclei also related to the visual system (the nucleus commissura posterior and the Nucleus pretectalis periventricularis pars dorsalis).  

Our results show that in the chick both the rho1- and rho2-subunit transcripts are present in the cerebellum, the optic tectum, the epithalamus and the Nucleus pretectalis.  

Neurons in the Nucleus pretectalis superficialis pars magnocellularis (PSm) in the common carp are known to send fibers to the corpus mamillare (CM) and the nucleus lateralis valvulae (NLV).  

Our data demonstrate that the ICo, an important site mediating the activation of vocal behavior in all birds, receives afferents from several important higher centers: the Nucleus pretectalis, the tuberoinfundibular hypothalamic region, the dorsal thalamus, the preoptic region and the paleostriatal region.  

Neurons of two nuclei previously shown to be sources of tectal input, the Nucleus pretectalis (PT) and the intergeniculate leaflet (IGL; Brecha, 1978), were found to be NPY+.  

Serotonin-IR fibers and terminals were found to be very broadly distributed within the brain and were particularly prominent in several structures of the telencephalon (archistriatum pars dorsalis, nucleus taeniae, area parahippocampalis, septum), diencephalon (nuclei preopticus medianus, magnocellularis, nucleus geniculatus lateralis pars ventralis, nucleus triangularis, Nucleus pretectalis), mesencephalon-rhombencephalon (superficial layers of the optic tectum, nucleus ectomamillaris, nucleus isthmo-opticus and in most of the cranial nerve nuclei).  

In addition, a few stained neurons were scattered in the nucleus of the posterior commissure and in Nucleus pretectalis superficialis pars magnocellularis.  

The distribution study displayed that these conditions were responsible for a heterogeneous binding pattern as shown by elevated receptor levels being located in visual brain centers, such as the stratum opticum, Nucleus pretectalis, and nucleus geniculatus lateralis, pars ventralis, while lower values were found in the nucleus lateralis hypothalami and nucleus isthmi pars magnocellularis.  

In addition to known contralateral retinorecipient regions, CTb-immunoreactive fibers and presumptive terminals were found in several ipsilateral regions, such as the nucleus of the basal optic root, ventral lateral geniculate nucleus, intergeniculate leaflet, nucleus lateralis anterior, area pretectalis, and Nucleus pretectalis diffusus.  

The cytoarchitecture, fiber connections, and ultrastructure of the Nucleus pretectalis superficialis pars magnocellularis (PSm) were studied in cypriniform teleosts (Cyprinus carpio).  

pretectalis and pretectalis periventricularis dorsalis; neurokinin A immunoreactive fibres in the nuclei pretectalis superficialis parvicellularis and magnocellularis and pretectalis periventricularis dorsalis; galanin immunoreactive fibres in the nuclei pretectalis superficialis parvicellularis, pretectalis centralis and pretectalis periventricularis dorsalis; and neurotensin immunoreactive fibres in the Nucleus pretectalis periventricularis dorsalis.  

No labeled cell bodies were seen in ipsilateral Nucleus pretectalis superficialis, pars magnocellularis, where they are seen in percomorphs.  

Additionally, the cytoarchitecture of the three synencephalic nuclei present in Clupea, the presence of small cells in Nucleus pretectalis superficialis pars parvicellularis and of larger, scattered cells in Nucleus pretectalis superficialis pars magnocellularis, the presence of large cells in the dorsal accessory optic nucleus that form a rostrocaudally oriented column, and the feature of a small, cell-sparse ventral accessory optic nucleus are plesiomorphic. Apomorphic features include the presence of a single, large, circular lamina that surrounds a central neuropil in all but the most caudal part of nucleus anterior, a lack of bilateral asymmetry in the habenular nuclei, the relatively small size of the periventricular nucleus of the posterior tuberculum, the presence of two, distinguishable caudomedial nuclei in the posterior tuberculum, elongation and folding of the neuropil of Nucleus pretectalis superficialis pars parvicellularis, and the relatively large size of Nucleus pretectalis superficialis pars magnocellularis and the posterior pretectal nucleus..  

In the adult brain TH-ir neurons were observed in the telencephalon (in the olfactory bulbs and the ventral telencephalic region), the diencephalon (in both the parvicellular and magnocellular portions of the preoptic nucleus, the suprachiasmatic nucleus, the ventromedial thalamic nucleus, the posterior tuberal nucleus, the organon vasculosum hypothalami, the lateral recess nucleus and the dorsal periventricular region of the medial lobe recess), the pretectal region (Nucleus pretectalis periventricularis), the isthmal region (locus coeruleus) and the medulla oblongata (in the area postrema, nucleus solitarius, the reticular area of the vagal region, and the reticular nucleus of the octaval region).  

The distribution of calbindin D-28K (CaBP28K) fibers and cell bodies in the Nucleus pretectalis superficialis magnocellularis of the Salmo gairdneri was studied using a monoclonal antibody and the avidin-biotin-peroxidase method. In addition, a high density of cell bodies CaBP28K-positive was also observed in the Nucleus pretectalis superficialis magnocellularis.  

Nucleus pretectalis was identified as a major target of rotundal efferents as well as a significant input to nucleus rotundus. The presence of a pretectal nucleus with neural connections and topographic location similar to Nucleus pretectalis of Caiman has been described in lizards and pigeons.  

In normal adult brains, neuropeptide Y-positive cells and processes were present in the Nucleus pretectalis, the nucleus of the basal optic root, the nucleus of the marginal optic tract, and the visual Wulst.  

Analysis of autoradiograms made with computer-assisted microdensitometry and pseudocolor image-enhancement techniques revealed that the greatest uptake of 2-DG occurred in the pretectal region, which included the large-celled nucleus lentiformis mesencephali (nLM), Nucleus pretectalis, and pretectal gray.  

The distribution of calbindin D-28K (CaBP28K) cell bodies and fibers in the Nucleus pretectalis superficialis parvicellularis of the rainbow trout was studied using a monoclonal antibody and the avidin-biotin-peroxidase method. The distribution and orientation of the immunoreactive cell bodies in the Nucleus pretectalis superficialis parvicellularis suggests that the neurons might be interneurons and/or projecting neurons..  

Jerk neurons were found throughout the whole superficial pretectum, but preferentially in an area that corresponds to the nucleus of the optic tract (NOT) and the Nucleus pretectalis posterior (NPP).  

Based on cytoarchitectural and HRP results, the pretectum of the adult hen was divided into the following eight nuclei: nucleus principalis pretectalis (P), nucleus subpretectalis (SP), nucleus principalis precommissuralis (PPC), nucleus medialis pretectalis (PTM), Nucleus pretectalis dorsalis (APd), nucleus area pretectalis (AP), nucleus spiriformis lateralis (SPL), and nucleus spiriformis medialis (SPM).  

Ventral hemiretinal fibers are mapped, however, onto the dorsal part of the Nucleus pretectalis superficialis pars parvocellularis, the rostral part of the dorsal accessory optic nucleus, the entire Nucleus pretectalis periventricularis pars ventralis and the dorsomedial portion of the optic tectum. In contrast, dorsal hemiretinal fibers are mapped onto the ventral part of Nucleus pretectalis superficialis pars parvocellularis, the entire dorsal accessory optic nucleus and the ventrolateral portion of the optic tectum. The pars parvocellularis of Nucleus pretectalis superficialis is a simple, unfolded, and nonlaminar structure in Pantodon.  

Afferent sources to the NLV were the Nucleus pretectalis superficialis pars magnocellularis (Northcutt and Braford, '84: Brain Res.  

The areas from which the various nuclei derived are reported together with the order of their appearance, the earliest being the nucleus geniculatus lateralis, the Nucleus pretectalis, the nucleus of the torus lateralis hypothalami, the nucleus preglomerulosus and the nucleus diffusus of the lateral lobes, all of were beginning to be distinguishable in 9 mm embryos.  

In the brainstem, terminal fields were observed in the ventral lamella of the inferior olive (OI), the parabrachial nuclei (PB) of the dorsolateral pons, the intercollicular nucleus (ICo) of the midbrain, and the Nucleus pretectalis diffusus (PD).  

The highest concentration of [ 3H]-WB4101 was observed in the Nucleus pretectalis, followed by the nucleus brachium conjunctivum descendens. Concentrations of [ 3H]-DHA binding higher than 300 fmoles/mg protein were observed in the paleostriatum, the external part of Nucleus pretectalis, the nucleus isthmi parvocellularis, the nucleus mesencephalis lateralis pars dorsalis, the dorsal nucleus of oculomotor center, and the molecular layer of cerebellum.  

The major brain structures that bind all three of the ligands are hippocampus; hyperstriatum dorsalis; hyperstriatum ventralis; nucleus lentiformis mesencephali; Nucleus pretectalis, some layers of the optic tectum; nucleus mesencephalicus lateralis; pars dorsalis; locus ceruleus; and all cranial motor nuclei except nucleus nervi hypoglossi.  

A high density of specific binding sites was present in the medial posterior hypothalamic nucleus, the superficial layer of the optic tectum, the area ventralis of Tsai (AVT), the Nucleus pretectalis, the habenula, the nucleus of Darkschewitch and the nucleus interstitialis.  

D2 but not D1 receptors were present in the tectum and Nucleus pretectalis.  

Highest densities of binding sites were observed in the optic tectum, in the Nucleus pretectalis, the nucleus intercollicularis and the substantia gelatinosa of the spinal cord.  

At middiencephalic levels, immunoreactive cells are present in the ventral thalamus, Nucleus pretectalis periventricularis, pars ventralis, and paraventricular organ pars anterioris.  

After a localized lesion was made within the posterior commissure, dense degenerated terminals were distributed in the most rostral part of the Nucleus pretectalis posterior, the nucleus of posterior commissure, the interstitial nucleus of Cajal, and the central tegmental field. A medium amount of degenerated terminals were observed in the Nucleus pretectalis anterior (pars reticularis), the dorsal part of the periaqueductal grey at its most rostral levels, the caudolateral parts of the Nucleus pretectalis posterior and the nucleus of optic tract, the H field of Forel, parts of the somatic cell columns of the oculomotor nucleus and the trochlear nucleus. However, the amount of degenerated terminals was very small in the Nucleus pretectalis medialis and the Nucleus pretectalis olivaris. The number of labeled cells appeared roughly proportional to the amount of degenerated terminals of the posterior commissural fibers described above with the apparent exception of the Nucleus pretectalis anterior, pars reticularis, where only a few labeled cells were identified.  

Mesencephalic cell groups consisted of the Nucleus pretectalis, the nucleus fasciculi longitudinalis medialis, and the nucleus ruber.  

Fiber connections of the so-called nucleus geniculatus lateralis (or the Nucleus pretectalis superficialis pars parvocellularis) in a teleost, Navodon modestus, were examined by means of the horseradish peroxidase (HRP) tracing method.  

Bilateral pupillary constriction was evoked with a low threshold current intensity by stimulation of the Nucleus pretectalis medialis, Nucleus pretectalis olivaris, rostral part of the Nucleus pretectalis posterior, the most rostral part of the periaqueductal grey and the nucleus of posterior commissure. Bilateral pupillary dilation was induced with a low threshold current intensity by stimulating the Nucleus pretectalis anterior, caudal periaqueductal grey and the midbrain tegmentum.  

The anterior sigmoid and rostral coronal gyrus projected amply onto the ventrolateral part of the Nucleus pretectalis anterior and to a large part of the ventrocaudal part of the Nucleus pretectalis posterior. The posterior sigmoid gyrus rostral to the postcruciate dimple and the caudal part of the coronal gyrus also projected to the Nucleus pretectalis anterior.  

Confirming the findings of Reiner and Karten (1978) characteristic accumulations of cells were seen in the nucleus opticus tegmenti, in the ipsilateral mesencephalic tegmentum and lateral and ventral to the ipsilateral Nucleus pretectalis.  

Prominent concentrations of the serotonin immunoreactive fibers were found in the lateral portion of the striatum, the ventral portion of the septum, the nucleus corporis geniculati lateralis, the Nucleus pretectalis, the nucleus isthmi parvocellularis, the optic tectum, and the lateral edge of the reticular formation of the brainstem.  

The optic fiber was found to partially decussate at the chiasm and to project to 5 contralateral regions: (1) hypothalamus (area optica hypothalami); (2) thalamus (area optica dorsalis thalami, area optica mediale thalami, nucleus thalamicus tractus optici marginalis, nucleus laminaris ventralis); (3) pretectum (Nucleus pretectalis ventralis, nucleus commissurae posterioris, nucleus intercalaris lateralis); (4) optic tectum (superficial layers); and (5) mesencephalic tegmentum (area optica accessoria).  

Saccades were induced from relatively broad regions of the rabbit's mesodiencephalon except for tractus opticus, a part of nucleus lateralis posterior thalami and some parts of Nucleus pretectalis anterior. Nystagmus was induced from tractus opticus, Nucleus pretectalis anterior and nucleus lateralis posterior thalami.  

The core contains thin and thick myelinated fibers, which originate in the optic tectum and in the Nucleus pretectalis, respectively. S terminals degenerate after ipsilateral ablation of the optic tectum, whereas F terminals degenerate after destruction of the Nucleus pretectalis..  

The following measurements were taken on the visual system in 13 species of butterflyfishes (family Chaetodontidae): volume and cell density of the nucleus geniculatus lateralis, nucleus corticalis, and Nucleus pretectalis; and width of the stratum opticum-stratum fibrosum et griseum superficiale. Tests for correlations between these components showed that the volumes of the Nucleus pretectalis and nucleus corticalis are positively correlated. A possible spurious positive correlation between the sizes of the Nucleus pretectalis, nucleus corticalis, stratum opticum-stratum fibrosum et griseum superficiale and total body length was also demonstrated..  

Terminations were seen contralaterally in the suprachiasmatic nucleus, the dorsal and ventral lateral geniculate nuclei (extensive), the pretectal nuclei, including the nucleus posterodorsalis (a very heavy input), the nucleus lentiformis mesencephali, nucleus geniculatus pretectalis, and Nucleus pretectalis, the superficial layers of the optic tectum, including the stratum zonale, the stratum opticum, the stratum griseum et fibrosum centrale and the upper portion of stratum griseum centrale, and the basal optic nucleus.  

Ipsilateral tectal afferents include the area dorsalis centralis of the forebrain, the nucleus dorsalis lateralis of the thalamus, the area pretectalis, the Nucleus pretectalis, a nucleus in the rostral mesencephalic tegmentum, the torus longitudinales, the torus semicircularis, a dorsolateral tegmental nucleus, the nucleus isthmi, and a rostral cell group of the nucleus motorius tegmenti. Comparison of results in a series of tectal HRP injections which differed in depth, tangential extent, and location indicated that projections from the area pretectalis, Nucleus pretectalis, and nucleus isthmi terminate in the stratum fibrosum et griseum superficiale of the tectum. Projections from the area and Nucleus pretectalis tend to terminate in the rostral tectum, and those from the contralateral tectum, torus semicircularis, dorsolateral tegmental nucleus, and nucleus motorius tegmenti terminate preferentially in the caudal tectum. HRP injections in the cerebellum labeled cells bodies in the area pretectalis, Nucleus pretectalis, and the nucleus of the posterior commissure.  

Very large and multipolar neurons are also labeled in the ipsilateral Nucleus pretectalis.  

After crossing, retinal projections distribute to the area preoptica, the thalamus dorsalis pars lateralis, the thalamus ventralis pars lateralis, the corpus geniculatum laterale, the Nucleus pretectalis, and the superficial layers of the tectum mesencephali.  

Ascending projections were found bilaterally to 3 pretectal nuclei -- the superficial pretectal nucleus, Nucleus pretectalis centralis and Nucleus pretectalis profundus -- and to a number of targets which lie further rostrally -- the central posterior nucleus, dorsal posterior nucleus, accessory optic nucleus, nucleus ventralis lateralis, nucleus of the ventral optic tract, rostral part of the preglomerular complex, suprachiasmatic nucleus, anterior thalamic nucleus, nucleus ventralis medialis, nucleus intermedius, nucleus prethalamicus and rostral entopeduncular nucleus.  

The Nucleus pretectalis remains comparatively large in size and divided into medial and lateral parts.  

Responses to optic tectum stimulation in Nucleus pretectalis exhibited the shortest latency.  

Ascending ipsilateral projections to pretectal-diencephalic areas exit the tectum rostrally and laterally and terminate in the area pretectalis (AP), lateral geniculate (LGN), Nucleus pretectalis (NP), and nucleus rotundus (NR).  

Following an autoradiographical study on the projections from the feline sensorimotor cortex (representation of the limbs) to the brain stem, new projections to Nucleus pretectalis posterior, the coerulear nuclei, nuclei corporis pontobulbares, nucleus intertrigeminalis, nucleus f, x and z of the vestibular nuclear complex, nucleus parvocellularis compactus, nucleus parasolitarius, nuclei insulae cuneati laterales, the nuclei of the raphé, nucleus reticularis lateralis and nucleus fastigii were found besides the well known projections to the tectal nuclei, the reticular formation, nucleus ruber, griseum pontis, the sensory trigeminal nuclei and the dorsal column nuclei.  

The Nucleus pretectalis is the largest and the best developed of all the elements of the posterior thalamic nuclear group.  

Contralaterally, the retina projects to the preoptic nucleus of the hypothalamus, and, via the medial optic tract, to the dorsal thalamus, medial ventral thalamic nucleus, Nucleus pretectalis profundus pars ventralis and pars dorsalis, and the medial portion of the deep layers of the central zone in the optic tectum. The dorsal optic tract projects to the lateral ventral thalamic nucleus, Nucleus pretectalis centralis, and the superficial white and gray zone of the optic tectum. The ventral optic tract terminates in the nucleus of the ventral optic tract, the lateral and medial ventral thalamic nuclei, Nucleus pretectalis superficialis, Nucleus pretectalis centralis, Nucleus pretectalis profundus pars ventralis, the basal optic nucleus, and the superficial white and gray zone of the optic tectum. Ipsilateral projections are to similar sites, except for an absence of inputs to the lateral ventral thalamic nucleus from the dorsal tract and to the Nucleus pretectalis superficialis, Nucleus pretectalis profundus pars ventralis, and the basal optic nucleus from the ventral tract.  

Contralateral projections were traced to the lateral geniculate nucleus, Nucleus pretectalis, accessory optic nucleus, nucleus corticalis, nucleus opticus hypothalamicus and the superficial layers of the optic tectum (strata opticum, fibrosum and griseum superficiale, and the cellular zone of griseum centrale).  

- Without afferent optic pathways there is no significnat change in cellular components of nucleus lateralis anterior, nucleus geniculatus lateralis ventralis, nucleus griseus tectalis, nucleus rotundus and Nucleus pretectalis principalis.  

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