Infundibular Nucleus


FRAs were present in the nuclei of a few astrocytes in the median eminence and infundibular nucleus of the tuber.  

We propose that neurons expressing KiSS-1, NKB, substance P, dynorphin and ERalpha mRNA in the infundibular nucleus play an important role in sex-steroid feedback on gonadotropin secretion in the human..  

In Experiment 4, central NPVF treatment was associated with decreased c-Fos immunoreactivity in the lateral hypothalamus, whereas c-Fos immunoreactivity in the dorsomedial nucleus, infundibular nucleus (homologue to the mammalian arcuate nucleus) and ventromedial nucleus was increased.  

The push-pull perfusions of the infundibular nucleus-median eminence (IN/ME) were made in lactating ewes (n=7) twice, to identify dopamine (DA)-derived salsolinol and the changes in its extracellular concentration in response to suckling.  

The majority of these juxtapositions were found in the infundibular nucleus/median eminence where NPY-IR fiber varicosities often covered a significant surface area of the GHRH neurons.  

To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR.  

Finally, POMC mRNA expression was characterized in the hypothalamic infundibular nucleus.  

Visfatin-treated chicks had increased c-Fos immunoreactivity in the lateral hypothalamus, decreased reactivity in the ventromedial hypothalamus and the dorsomedial hypothalamus, infundibular nucleus, periventricular nucleus, paraventricular nucleus were not affected.  

In line with these light microscopy data, ultrastructural examination of GnRH-immunoreactive neurones showed numerous glial cells in direct apposition to pre-embedding-labelled GnRH cell bodies and/or dendrites in the infundibular nucleus, whereas postembedding immunogold-labelled GnRH nerve terminals were often seen to be enwrapped by glial cell processes in the median eminence.  

Here, we report the photoperiodic regulation of the insulin receptor (IR) gene in the infundibular nucleus (anatomically homologous to the mammalian arcuate nucleus) of the Japanese quail. These results suggested that the photoperiodic regulation of the IR mRNA in the infundibular nucleus is mediated by testosterone from the testes.  

Unlike in rodents, we observed that CART is absent from the perikarya and axons of alpha-MSH-synthesizing neurons, but expressed in approximately one third of NPY/AGRP neurons in the human infundibular nucleus. The anatomy of CART-containing neurons in the human infundibular nucleus differs markedly from that observed in the rodent brain, raising the question whether the colocalization of CART with orexigenic NPY and AGRP neurons is associated with an orexigenic role of CART in the human brain..  

In monkeys, our objective was to evaluate the effects of ovariectomy and hormone replacement on neurons expressing KiSS-1 mRNA in the infundibular nucleus. RESULTS: Examination of human hypothalamic sections revealed that KiSS-1 neurons were located predominantly in the infundibular nucleus. In the infundibular nucleus of postmenopausal women, there was a significant increase in the size of neurons expressing KiSS-1 mRNA and the number of labeled cells and autoradiographic grains per neuron. Similar to postmenopausal women, ovariectomy induced neuronal hypertrophy and increased KiSS-1 gene expression in the monkey infundibular nucleus.  

In addition to the area of the suprachiasmatic nucleus (SCN), a number of novel sites, including the paraventricular nucleus (PVN), periventricular nucleus, supraoptic nucleus (SON), sexually dimorphic nucleus, the diagonal band of Broca, the nucleus basalis of Meynert, infundibular nucleus, ventromedial and dorsomedial nucleus, tuberomamillary nucleus, mamillary body, and paraventricular thalamic nucleus were observed to have neuronal MT1 receptor expression.  

D2 immunoreactivity is prominent in glial cells of the infundibular nucleus/median eminence region and in tanycytes lining the third ventricle.  

D2 enzyme activity was detectable in the infundibular nucleus/median eminence (IFN/ME) region coinciding with local D2 immunoreactivity in glial cells.  

The population of NPY-ir neurons located in the infundibular nucleus exhibited a prominent expression of NPY immunoreactivity in the perikarya and fibres only during the preovulatory phase. The present study suggests that NPY-ir neurons present in the infundibular nucleus can play a role in the preovulatory GnRH discharge from the median eminence..  

The aim of the current study was to analyze the putative relationship of the orexigenic NPY and anorexigenic alpha-MSH systems in the infundibular nucleus of the human hypothalamus, the analogue of the rodent arcuate nucleus. Both NPY- and alpha-MSH-immunoreactive (IR) neurons were embedded in dense, intermingling networks of NPY- and alpha-MSH-IR axons in the human infundibular nucleus. In summary, the present data demonstrate that these two antagonistic, feeding-related neuronal systems are interconnected in the infundibular nucleus, and the neuronal wiring possesses an asymmetric character in the human hypothalamus..  

The sheep pituitary stalk presents neurones containing neuropeptides such as neuropeptide-Y or beta-endorphin, which are also found in the deep part of the infundibular nucleus. This feature is well illustrated by the number of neuropeptide-Y labelled neurones, that increases in the lateral part of the infundibular nucleus of undernourished ewes and decreases in the ventral part of overfed ewes. Conversely, after 24 hours of food deprivation, the number of neuropeptide-Y-immunolabelled neurones is unchanged in the sheep infundibular nucleus, whereas increased levels of this neuropeptide are described, in rats, by radioimmuno-assay.  

NPY content in the paraventricular nucleus (PVN) and infundibular nucleus significantly increased during fasting, and NPY content of the PVN was restored to pre-fasting levels after 24-h refeeding.  

Males had nearly twice as many VIP-immunoreactive (ir) neurons in the infundibular nucleus than did females, and birds of the WS morph had more densely stained VIP-IR in the median eminence than TS birds.  

RESULTS: D2 immunoreactivity is prominent in glial cells of the infundibular nucleus/median eminence, blood vessels, and cells lining the third ventricle. By contrast, both D3 and MCT8 are expressed by neurons of the paraventricular (PVN), supraoptic, and infundibular nucleus (IFN).  

The galanin-immunoreactive neurones were counted in three areas, the preoptic area, the bed nucleus of the stria terminalis and the infundibular nucleus, using a computerized image analysis system. There was no change in the mean number of galanin-immunoreactive (GAL-ir) neurones in the infundibular nucleus (37 +/- 12 neurones/section in treated animals and 31 +/- 11 in controls) or in the bed nucleus of the stria terminalis (22 +/- 5 neurones/section in treated animals and 16 +/- 4 in controls), but the number of GAL-ir neurones was higher in the preoptic area in treated than in control ewes (35 +/- 4 versus 14 +/- 10, P < 0.001). These results indicate that oestradiol might act directly on a GAL-ir neuronal population situated in the preoptic area, without any effect on the GAL-ir neurones of the infundibular nucleus or the bed nucleus of the stria terminalis.  

To examine the role of gamma-aminobutyric acid (GABA)B receptor mediating systems in the ventromedial hypothalamus-infundibular nucleus region (VMH/NI) of anoestrous ewes in controlling gonadotropin-releasing hormone (GnRH) release, the extracellular concentrations of GnRH, beta-endorphin, norepinephrine, dopamine, 4-hydroxy-3-methoxy-glycol and 3,4-dihydroxy-phenylacetic acid were quantified during infusion of baclofen or phaclofen (agonist and antagonist of GABAB receptors, respectively) in this structure.  

In the present study, MCH1R was shown, by immunocytochemistry, to be present in the human infundibular nucleus/median eminence, paraventricular nucleus, lateral hypothalamic area, and perifornical area, although in the latter two regions, only a few MCH1R-containing cells were found. A significant 1.6 times increase in the number of MCH1R cell body staining was found in the infundibular nucleus in postmortem brain material of cachectic patients, compared with matched controls, supporting a role for this receptor in energy homeostasis in the human..  

the supraoptic nucleus (SON), the infundibular nucleus (INF), the medial mamillary nucleus (MMN).  

Staining intensity showed strong interindividual variation but was consistently present in the infundibular nucleus, paraventricular nucleus, and supraoptic nucleus. Neuropeptide Y and proopiomelanocortin mRNA-positive cells in the infundibular nucleus, which were studied in three other hypothalami, appeared not to express TRs, and thus, the neurons expressing TRs in the human mediobasal hypothalamus remain to be characterized..  

In postmenopausal women, the neurons of the infundibular nucleus hypertrophy and become hyperactive because of the disappearance of the estrogen feedback and contain hyperactive peptidergic neurons.  

In the diencephalon, in addition to somatostatin-immunoreactive cells in the ependyma, positive cell bodies were also found in the periventricular preoptic nucleus, the infundibular nucleus, the epiphysis, and the subcommissural organ.  

A moderate density of cells was observed in the perifornical nucleus, infundibular nucleus, tuberomammillary nucleus, and lateral tuberal nucleus.  

We investigated the photoperiodic response of serotonin- and galanin (GA)- immunoreactive (ir) cells in the paraventricular organ (PVO) and infundibular nucleus (IF) of the Japanese quail and the interaction of these cells with gonadotropin-releasing hormone (GnRH)-ir neurons in the hypothalamus.  

We report a significant increase ( approximately 100%) in the numbers of autoradiographic grains/NPY neuron in the retrochiasmatic area and infundibular nucleus of older women.  

The expression of estrogen receptor (ER)alpha and -beta in the infundibular nucleus of the hypothalamus was studied immunocytochemically in 28 control subjects and 14 patients with Alzheimer's disease (AD). All AT8-positive neurons in the infundibular nucleus contained alphaMSH as a marker for proopiomelanocortin neurons.  

This area contains numerous neurons expressing the estradiol receptor alpha, distributed in the ventromedial nucleus (VMN) and the infundibular nucleus (IN).  

NKB neurones in the infundibular nucleus of ovariectomized monkeys were larger, more numerous and displayed increased levels of NKB mRNA compared to those of intact controls.  

Our results demonstrate that this short E2 treatment significantly decreased both the mean number of silver grains per POMC-containing cell (35%) and the mean number of POMC-cells (38%) in the ovine infundibular nucleus, whereas the treatment had no effect on preproNPY mRNA expression.  

In birds, the mediobasal hypothalamus (MBH) including the infundibular nucleus, inferior hypothalamic nucleus, and median eminence is considered to be an important center that controls the photoperiodic time measurement.  

Vehicle-injected ovariectomized rabbits showed PR-immunoreactive cells only in the infundibular nucleus (IN) and nucleus X (lateral to the ventromedial hypothalamic nucleus).  

alpha-MSH and AGRP were expressed in the infundibular nucleus of POMC and NPY neurons, respectively, in the brain of Japanese quail.  

In situ hybridization revealed strong signals for AGRP and POMC mRNAs in the infundibular nucleus (IN), for prepro-orexin in the lateral hypothalamic area (LHy) and periventricular hypothalamic nucleus, and for VIP in the LHy.  

In sheep, essentially all the neurokinin B (NKB) neurones of the infundibular nucleus express oestradiol receptor alpha, and analysis of female and male brains has revealed an exceptionally marked female-dominant sex difference in the numbers of NKB neurones in the infundibular nucleus. After cloning a specific ovine NKB antisense riboprobe, we examined the effects of a short oestradiol treatment (4 h subcutaneously) on the expression of NKB mRNA in the caudal part of the infundibular nucleus of progesterone-primed ovariectomized ewes.  

Observations in the infundibular nucleus have, however, indicated that in this brain area the hyperactivity resulting from a lack of estrogens in the menopause seems to protect females against Alzheimer changes, in contrast to males.  

DESIGN: We examined GHRH neurones in the infundibular nucleus/median eminence complex of control subjects (n = 26, including four children), PWS (n = 6) and non-PWS (n = 4) obese adults and PWS children (n = 2), by quantitative immunocytochemistry, using postmortem material.  

Long-term undernutrition enhanced the number of galanin neurones located in the infundibular nucleus and the dorsal hypothalamic area (DHA), refeeding resulted in an increase of neurones in the DHA and preoptic area, but short-term starvation had no effect on any galanin subpopulations.  

Similar results were obtained with both antibodies used: dense aggregations of ERalpha-immunoreactive (IR) neurons were found in the infundibular nucleus (IN), the medial preoptic area (POA), the bed nucleus of the stria terminalis (BNST), and some nuclei of the amygdala.  

GHRH perikarya were restricted to the infundibular nucleus and the ventral ventromedial nucleus and although frequently surrounded by numerous progesterone receptor-immunoreactive cells, none was colocalized.  

Immunoreactive neurons were detected in telencephalic, diencephalic and mesencephalic areas such as dorsal cortex, subfornical organ, paraventricular nucleus, recessus infundibular nucleus, nucleus of the oculomotor nerve and nucleus of the trigeminal nerve.  

Mesotocinergic perikarya were also present in the recessus infundibular nucleus and ependyma near to paraventricular organ.  

Anatomically, both Y1 and Y5 have high mRNA expression levels in the infundibular nucleus which is the homologous structure of the hypothalamic arcuate nucleus in mammals.  

This revealed a strong signal in the infundibular nucleus (IN).  

Because NPY and agouti-related protein (AGRP) are co-contained in neurons of the human infundibular nucleus, we used AGRP as a marker of NPY fibers originating exclusively from the infundibular nucleus. Only a small proportion of CRH neurons in the PVN was contacted by AGRP-IR axon varicosities, suggesting that NPY-IR innervation of CRH neurons in the PVN derive mainly from regions outside the infundibular nucleus.  

In the hypothalamus a subpopulation of paraventricular and infundibular nucleus neurons were strongly immunoreactive for p42IP4.  

Using combined ICC and in situ hybridization, AGRP, but not POMC, was colocalized with NPY in infundibular nucleus neurons. infundibular nucleus (including median eminence) NPY ICC staining or mRNA expression, and AGRP ICC staining, increased with premorbid illness duration.  

In colchicine-treated animals, large populations of NPY-immunoreactive (-ir) neurons were observed in a ventral and a lateral subpopulation of the infundibular nucleus (IN), in the median eminence, the pituitary stalk, and the dorsomedian and dorsocaudal nuclei.  

On the basis of the Golgi technique, as well as the Nissl and Kl├╝ver-Barrera methods, four types of neurons were distinguished in the ventromedial nucleus (VMH) and infundibular nucleus (Ni): 1.  

Immunolabeled perikarya were relatively few and were mostly scattered through the anterior (preoptic) and mediobasal regions (infundibular nucleus) of the hypothalamus. They exhibit high densities in the preoptic region, the organum vasculosum of lamina terminalis, infundibular nucleus and median eminence.  

The largest number of perikarya-expressing NPY mRNA was found within the mediobasal hypothalamus, including the infundibular nucleus, inferior hypothalamic nucleus, and median eminence. Following food deprivation for four days, perikarya-expressing NPY mRNA and peptide were markedly increased in the mediobasal hypothalamus and particularly so in the infundibular nucleus.  

Two distinct populations of the immunoreactive NPY perikarya were found, one in the infundibular nucleus; and the other in areas of diencephalon adjacent to the rostral hypothalamus. Long-term feeding the protein restricted diet caused a prominent expression of the immunoreactive material solely in the hypothalamic NPY neurones, particularly in those located in the entire periventricular area and in the infundibular nucleus.  

Our previous studies in postmortem brain material showed decreased thyrotropin-releasing hormone (TRH) messenger RNA (mRNA) in the paraventricular nucleus (PVN) of patients with NTI, suggesting a role for TRH cells in the persistence of low TSH levels in NTI.In the present study, we hypothesized that changes in neuropeptide Y (NPY) input from the infundibular nucleus (IFN) to TRH cells in the PVN might be a determinant of decreased TRH expression in NTI.  

We found CART cell bodies in the PVH, in the SON, in the LHA, in the Arc (infundibular nucleus) and in the DMH.  

The high density of fibers was located in the suprachiasmatic nucleus, the infundibular nucleus (INF), the tuberomamillary nucleus (TM) and the supra- and pre-mamillary nuclei.  

In contrast to the rat, the lemur exhibited marked labelling in the infundibular nucleus, the periventricular nucleus and the pars tuberalis of the pituitary gland, whereas no labeling was detectable in the ventromedial nucleus and the lateral hypothalamic area.  

An intermediate nuclear staining was found in the diagonal band of Broca, sexually dimorphic nucleus of the preoptic area, paraventricular nucleus, suprachiasmatic nucleus, ventromedial nucleus, and infundibular nucleus, whereas weaker labeling was found in the bed nucleus of the stria terminalis, medial preoptic area, dorsal and ventral zones of the periventricular nucleus, supraoptic nucleus, and nucleus basalis of Meynert.  

In contrast, the number of neurons expressing proopiomelanocortin (POMC) mRNA in the infundibular nucleus of older women is decreased. These data demonstrate that neuronal hypertrophy in older women is not accompanied by degeneration of the infundibular nucleus.  

By using antisera to N-terminal POMC, alpha-melanotropin and beta-endorphin, POMC-containing cells were observed in the cephalic lobe of the pituitary and immunopositive perikarya were localized in the infundibular nucleus and median eminence of the hypothalamus.  

During early premetamorphosis, ir perikarya were distributed in the ventral infundibular nucleus of the hypothalamus and in the posterocentral nucleus of the thalamus. In tadpoles at stages VIII-IX, a new group of VIP-labeled neurons was observed in the dorsal part of the infundibular nucleus.  

A conspicuous pathology, characterized by neurofibrillary tangles, a network of dystrophic neurites, and terminal-like vessel-associated processes, was identified in the infundibular nucleus which is located in the mediobasal tuber cinereum.  

In the ovariectomized ewes, galanin-immunoreactive neurones were mainly observed in the medial preoptic area and the infundibular nucleus.  

CARTir neurons were particularly abundant in the PVN, supraoptic nucleus (SON), infundibular nucleus, and premammillary nucleus, whereas the anterior, lateral, and posterior hypothalamic areas as well as the posterior nucleus displayed moderate immunoreactivity.  

NMDA also significantly induced Fos-like immunoreactivity (FLI) within the infundibular nucleus and median eminence, regions previously shown to express FLI after a photoperiodically driven LH rise.  

In contrast, HRT had no effect on the POMC system of neurons or the number of microglial cells in the infundibular nucleus. Finally, we found no evidence that HRT, in doses designed to mimic currently prescribed regimens, produces signs of estrogen toxicity in the primate infundibular nucleus..  

The number of POMC mRNA-containing neurons/section in the infundibular nucleus was reduced by 65% in postmenopausal women. The POMC neurons in the retrochiasmatic area were also distinct morphologically from those in the infundibular nucleus. Our findings provide evidence that the activity of hypothalamic POMC neurons is decreased in the infundibular nucleus of postmenopausal women.  

Part of the infundibular nucleus, the subventricular nucleus, contains hypertrophic neurokinin B neurons in postmenopausal women.  

One was the preoptic recess organ (PRO) in the prechiasmatic area, the other two were the paraventricular organ (PVO) and infundibular nucleus (IN) in the postchiasmatic area.  

The distribution of tyrosine hydroxylase (TH) and of galanin immunoreactive (IR) neurons were examined in the sheep infundibular nucleus. Neurons immunoreactive to TH alone were observed close to the third ventricle and in the rostral part of the infundibular nucleus. Thus, in sheep, the population of catecholaminergic neurons of the infundibular nucleus may be subdivided into different subpopulations according to their peptide content, but does not appear segregated as in rat and human..  

After castration, aromatase was significantly reduced in the medial preoptic area/anterior hypothalamus, periventricular preoptic area, lateral preoptic area/anterior hypothalamus, and infundibular nucleus/median eminence.  

Scarce fibers project to the suprachiasmatic nucleus, infundibular nucleus, posterior hypothalamic nucleus, and posterior part of the bed nucleus of the stria terminals.  

In stage VI tadpoles, new groups of immunopositive perikarya and nerve fibers appeared in the diencephalon, within the ventral infundibular nucleus and in the ventral area of the thalamus, as well as in the medial pallium. In stages XII-XIV of development, immunopositive perikarya were also present in the dorsal infundibular nucleus of the hypothalamus and ventrolateral area of the thalamus.  

Using immunohistochemistry, we have identified NPY-containing neurons in the infundibular nucleus and the internal layer of the median eminence in fetal hypothalami collected between 110 and 147 days gestation.  

Neurons displaying immunoreactivity for calbindin-D28k were especially numerous in the medial preoptic area and diagonal band nucleus, as well as in the magnocellular subdivision of the paraventricular nucleus, the suprachiasmatic nucleus, the supraoptic nucleus, the infundibular nucleus, the ventromedial nucleus and the mammillary bodies of the hypothalamus.  

At climax stages, immunoreactive fibers and perikarya (weakly stained) were identified in the interpeduncular nucleus and in the dorsal infundibular nucleus.  

We studied the distribution of neuropeptide Y (NPY) immunoreactivity in the infundibular nucleus and the hypophysis of the chimpanzee, gorilla, and orangutan. Using antibodies developed in rabbit against synthetic porcine NPY, we found numerous NPY-immunoreactive neuronal somata in the infundibular nucleus; this nucleus was also filled with short NPY-positive processes and an abundance of punctate structures that could be indicative of synaptic terminals.  

Median eminence activation appeared within glial cells, whereas activated infundibular nucleus cells were neuronal, providing support to the view that gonadotropin-releasing hormone (GnRH) release can be controlled at the terminals by glia.  

The relative distribution of P450arom mRNA (the 455-nt fragment) between brain areas of the adult (n = 3) was high in the bed nucleus of the stria terminalis > medial preoptic/anterior hypothalamus > amygdala; intermediate in the medial basal hypothalamus (infundibular nucleus, median eminence, ventromedial nucleus) > lateral preoptic/anterior hypothalamus; and low in the septum > lateral-dorsal-medial hypothalamus.  

Part of the arcuate nucleus of the hypothalamus (ARH), or tubero-infundibular nucleus, contains hypertrophic neurons in postmenopausal women.  

A highly significant increase in NPY neurons was found within the infundibular nucleus (IN) and the internal zone of the ME of SMZ-treated chicks compared to controls at 3 weeks of age.  

Perikarya immunoreactive to HA were localized in the dorsal infundibular nucleus of the hypothalamus.  

In brains of control and early infected rats, irIL-1 beta was only detected in fibers located in the hypothalamus, supraoptic and tractus optic nuclei and infundibular nucleus.  

A conspicuous pathology was identified, characterized by terminal-like processes contacting the neurohemal vasculature of the posterior median eminence and the adjacent infundibular nucleus.  

Dopaminergic cells elsewhere in the hypothalamus, including the infundibular nucleus, did not display AR immunoreactivity.  

NOS type 1 is expressed in preoptic and infundibular nucleus of hypothalamus.  

Pre-POMC cells are most numerous in the infundibular nucleus and retrochiasmatic area of the mediobasal hypothalamus; a few labeled cells are present within the boundaries of the ventromedial nucleus and infundibular stalk. Pre-PENK neurons are numerous in the infundibular nucleus, ventromedial nucleus, dorsomedial nucleus, caudal parvicellular portion of the paraventricular nucleus, tuberomammillary nucleus, lateral hypothalamus, and retrochiasmatic area.  

Three populations of 3 beta-HSD-immunoreactive cell bodies were observed in the hypothalamus, namely, in the rostral region of the preoptic nucleus, the dorsal infundibular nucleus, and the dorsal part of the ventral infundibular nucleus.  

Immunoreactive perikarya can be identified in the caudal diencephalon (paraventricular organ and infundibular nucleus), in the ventral mesencephalon (interpeduncular nucleus) and in the raphe of the rhombencephalon.  

Quantitative image analysis revealed that this effect of background adaptation is specific for suprachiasmatic neurons because no effect could be demonstrated of the background light condition on the ventral infundibular nucleus (immunocytochemistry) or the ventromedial thalamic nucleus (in situ hybridization).  

Immunoreactive neurons were identified in telencephalic, diencephalic and mesencephalic areas such as the cortex, nucleus caudatus, nucleus accumbens, amygdala, subfornical organ, paraventricular nucleus, hypothalamic dorsolateral aggregation, nucleus of the paraventricular organ, infundibular nucleus, pretectal nucleus, periventricular grey, reticular formation and nucleus of the raphe.  

A striking neuronal hypertrophy occurs in the infundibular nucleus of postmenopausal women. To determine the gender specificity of this response, we measured the areas of neuronal profiles in the infundibular nucleus of young (21, 32, and 41 years) and older (60, 61, and 68 years) men and compared them to data reported previously from the hypothalami of pre-(28, 32, and 40 years) and postmenopausal women (58, 62, and 74 years). There was also a significant increase in the density of hypertrophied neurons (> 226 microns 2 profile area) in the infundibular nucleus of older men. There was no difference in infundibular nucleus associated with an average neurons was significantly increased in the older men.  

Nuclear AR levels, on the other hand, were significantly elevated after T treatment (activated) only in the ventral medial nucleus (VMN) and infundibular nucleus/median eminence (P < 0.05). Physiological concentrations of T increased AA only in the VMN and infundibular nucleus-median eminence (P < 0.05).  

Beaded nerve fibers were observed coursing from the ventral infundibular nucleus to the external vascular layer of the median eminence.  

In the forebrain, labelled cell bodies occurred in the infundibular nucleus of the hypothalamus and some closely adjacent nuclei.  

In the hypothalamus, corticotropin-immunoreactive parvicellular perikarya were found in the infundibular nucleus and in dendritic projections to the infundibular recess.  

PR-immunoreactive cells were found throughout the ventromedial nucleus (VMN), in the area between the VMN and fornix, and in the medial portion of the infundibular nucleus.  

Neuronal hypertrophy occurs in a subpopulation of neurons in the infundibular nucleus of post-menopausal women.  

In animals pretreated with estradiol benzoate, the highest density of immunostained neurons was found throughout the infundibular nucleus, especially in the region of the mammillary recess of the third ventricle.  

We have previously described hypertrophy of neurons containing estrogen receptor mRNA in the infundibular nucleus of postmenopausal women. Finally, the numbers of labeled neurons/tissue increased 6-fold (SP) and 15-fold (NKB) in the postmenopausal infundibular nucleus.  

Scatchard analysis showed that in a guanosine triphosphate-sensitive region (preoptic area) and a guanosine triphosphate-insensitive area (infundibular nucleus), [ 125I]Tyr0-D-Trp8SRIF 14 bound to a single class of binding sites. Affinities were similar in both regions, not modified by guanosine triphosphate pretreatment and not different in the adult (1.5 +/- 1.2 nM vs 3.2 +/- 2.1 nM for preoptic area and infundibular nucleus, respectively) and infant (0.9 +/- 0.5 nM vs 2.4 +/- 1.7 nM for preoptic area and infundibular nucleus). Somatostatin 28 was twice as potent as somatostatin 14 to displace [ 125I]Tyr0-D-Trp8SRIF 14 binding in the preoptic area and infundibular nucleus. However, IC50s were 30 times lower in the preoptic area as compared with the infundibular nucleus. In adult as well as in infant, high densities were found mainly in the diagonal band of Broca, preoptic area and infundibular nucleus.  

Labeled fibers arising from the dorsal infundibular nucleus projected ventrolaterally to contribute to catecholaminergic innervation of the median eminence and pituitary.  

GRF- and GAL-IR cell bodies were demonstrated in the ventral part of the infundibular nucleus and dense aggregations of GRF- and GAL-IR fibers were seen in the external layer of the median eminence, closely surrounding portal vessels. Double-staining revealed that GRF and GAL were colocalized in cell bodies of the infundibular nucleus and in nerve fiber varicosities in the external layer of the median eminence.  

Following injections in the lateral, anterior, and posterior interposed cerebellar nuclei retrogradely labeled cells were present in the following areas (greatest to least concentration): lateral and dorsal hypothalamic areas, dorsomedial nucleus, griseum periventriculare hypothalami, supramammillary and tuberomammillary nuclei, posterior hypothalamic area, ventromedial nucleus and periventricular hypothalamus, around the medial mammillary nucleus, lateral mammillary nucleus, and infundibular nucleus.  

Computer microscopy and in situ hybridization were used to investigate neuronal hypertrophy in the infundibular nucleus of postmenopausal women. Finally, analysis of the infundibular nucleus from an oophorectomized 38-yr-old woman also revealed hypertrophied neurons containing ER mRNA.  

Within the hypothalamus, numerous LHRH-immunoreactive like (IL) cell bodies were found mainly in the ventral portion of the infundibular nucleus close to the median eminence and at a lower extent in the medial preoptic area.  

We found that, when administered in doses that suppressed serum LH, both testosterone (T) and estradiol (E) significantly increased LH-RH in the infundibular nucleus/median eminence.  

The histamine-immunoreactive cell bodies were located in a small area of the posterolateral hypothalamus, close to the dorsal infundibular nucleus, which contains catecholaminergic and serotonergic neurons.  

Immunoreactive neuronal perikarya were distributed in the MPOA, PVN and infundibular nucleus, with the largest numbers of GAP-like immunoreactive perikarya found in the infundibular nucleus.  

NPY-IR was detectable in the acid extracts of tissue samples prepared from all the hypothalamic regions studied, with the highest concentrations being found in the infundibular nucleus (325 +/- 53 fmol/mg wet weight of tissue) and the ventromedial nucleus (217 +/- 22 fmol/mg). The infundibular nucleus exhibited the greatest range of values (72-1,137 fmol/mg). Expressed as correlation coefficients (r), levels in the infundibular nucleus appeared to be most closely related to those of the ventromedial nucleus (VM; r = 0.89) and paraventricular nucleus (PV; r = 0.84). In addition, retrospective analysis of the clinical histories showed that all patients with very high NPY levels in the infundibular nucleus (621.0 +/- 107.7 fmol/mg; n = 8) had suffered from respiratory failure or severe dyspnea of at least 10 days duration prior to death.  

The most dense collections of PR-IR cells were found in the preoptic area, ventrolateral nucleus of the hypothalamus, and infundibular nucleus. Sequential treatment with estrogen plus progesterone further increased PR-IR cell number, in the preoptic area by 65%, in the ventrolateral nucleus by 38%, and in the infundibular nucleus by 49%.  

The distribution of neurons exhibiting somatostatin (SRIF)-, neuropeptide Y (NPY)-, beta-endorphin- and neurotensin (NT)-like immunoreactivity within the infundibular nucleus (NI) of the sheep, and the extent of coexistence of the above peptides within individual neurons of the NI were investigated with immunocytochemical techniques.  

CGRP-immunoreactive cell bodies were found in the supraoptic nucleus, paraventricular nucleus and infundibular nucleus. These findings indicate that CGRP exists in the cell bodies of the supraoptic nucleus, paraventricular nucleus and infundibular nucleus in the human hypothalamus and CGRP may play some roles in the endocrine and other functions of the human hypothalamus..  

The highest levels of ANF binding sites were found in the olfactory bulb, the dorsal pallium, the septum, the habenular nucleus, the dorsal infundibular nucleus, the interpeduncular nucleus, and in the tectum.  

In control subjects, LHRH immunoreactive (LHRH-IR) perikarya have been mainly observed essentially in the infundibular nucleus.  

Thyrotropin-releasing hormone-immunoreactive perikarya occurred mainly in the anterobasal periventricular area and dorsal extension of the preoptic nucleus, and in the lateral zone of the infundibular nucleus.  

Cell bodies with neurotensin-like immunoreactivity are seen maximally in the medial preoptic region, the infundibular nucleus, and the lateral hypothalamus.  

In brain tissue, the highest androgen receptor levels were found in the infundibular nucleus/median eminence (9.4 +/- 2.3 fmol/mg protein), ventromedial nucleus (6.3 +/- 1.7 fmol/mg protein) and periventricular area (4.9 +/- 1.3 fmol/mg protein).  

Compared to sexually unresponsive males, sexually responsive males had significantly higher concentrations of immunoreactive (ir) AVT in the dorsal preoptic area, optic tectum, ventral infundibular nucleus, and cerebrospinal fluid.  

Immunoreactive cell bodies were principally found in the dorsal and medial pallium, the medial septal nucleus, the ventrolateral and anteroventral areas of the thalamus, the lateral forebrain bundle, the posterolateral thalamic nuclei, the preoptic nucleus, the dorsal infundibular nucleus, and the anteroventral tegmentum nucleus of the mesencephalon. In addition, the amygdala, the infundibular nucleus, the median eminence, and most of the areas of the mesencephalon contained a moderate number of ANF-positive nerve processes.  

Most of the VIP-containing neurons are concentrated in the middle and caudal parts of the hypothalamus, with the greatest concentration of perikarya occurring in the medial and lateral part of the ventromedial hypothalamic nucleus and the infundibular nucleus.  

Brain regions, areas or nuclei found densely innervated by NPY-like immunoreactive fibers included the olfactory bulb region, septal area, organum vasculosum of the lamina terminalis, preoptic periventricular nucleus, hypothalamic periventricular nucleus, medial suprachiasmatic nucleus, subseptal (subfornical) organ, ventromedial hypothalamic nucleus, infundibular nucleus and nucleus tractus solitarius.  

Highest numbers of labeled cells were found in the anterior preoptic area, in the ventral infundibular nucleus, and in the pituitary.  

Appreciable numbers of immunoreactive perikarya were observed in the dorsal and medial pallium, the medial septal nucleus, the anteroventral and ventrolateral areas of the thalamus, the lateral forebrain bundle, the posterocentral and posterolateral thalamic nuclei, the preoptic nucleus, the dorsal infundibular nucleus and the anteroventral tegmental nucleus of the mesencephalon. Fibres were generally seen where cell bodies were observed, particularly in all regions of the pallium and septum nuclei, in the ventral thalamus, the infundibular nucleus and the tegmental area. Moderate numbers of fibres were also noted in several regions where cell bodies were absent, mainly in the amygdala and the infundibular nucleus, the median eminence and most mesencephalic regions.  

Cell bodies containing alpha-MSH-Li were observed in the medial basal hypothalamus, especially in the infundibular nucleus, the lateral hypothalamus and near zona incerta.  

In contrast, alpha-MSH immunoreactive neurons of the ventral infundibular nucleus did not contain any MCH-like peptide.  

The highest concentrations of LHRH were in the infundibular nucleus-median eminence and were 30 times greater than amounts measured in preoptic and medial hypothalamic nuclei. The LHRH contents of the infundibular nucleus-median eminence, ventral medial nucleus, and lateral hypothalamus were significantly lower in castrated males (P less than 0.05).  

In the hypothalamus, numerous ANF-positive cell bodies were located in the preoptic nucleus, the lateral forebrain bundle and the dorsal infundibular nucleus.  

Comparatively, a moderate number of cell bodies was observed in the dorsal infundibular nucleus and in the ventral thalamic area. Brightly immunofluorescent nerve bundles were found in the preoptic nucleus and in the ventral infundibular nucleus, coursing towards the internal zone of the median eminence and the pituitary stalk.  

The distribution pattern of adrenocorticotropin-like immunoreactivity (ACTH-LI) in cats using the avidin-biotin modification of an immunocytochemical method shows cell bodies containing ACTH-LI in the medial basal hypothalamus, especially in the infundibular nucleus.  

These fibers originated from the ventral infundibular nucleus, travelled via the median eminence to the pars intermedia.  

The highest concentrations of GHRH immunoreactivity (IR-GHRH) in the hypothalamus were found in the area of the infundibular nucleus (83 +/- 4 ng/mg protein; average +/- range).  

The highest concentration of IR-GHRH in the hypothalamus was in the infundibular nucleus, with lesser concentrations in the periventricular area and paraventricular and supraoptic nuclei. 2) The infundibular nucleus contains the greatest IR-GHRH regional concentration, in accord with immunohistochemical studies.  

After estrogen priming, many heavily labeled cells were observed in the following areas: ventrolateral striatum and amygdala, anterior preoptic area, ventral infundibular nucleus, laminar nucleus of the torus semicircularis, and anterior pituitary.  

Immunoreactive fibers were found in the infundibular nucleus and in various extrahypothalamic zones.  

Primary sites of posterior hypothalamic lesions included the premamillary area and the posterior nucleus, while the infundibular nucleus and the median eminence were entirely spared.  

Immunoreactive perikarya are localized to hypothalamic infundibular nucleus, giving rise to several distinct projections.  

GLI perikarya are few in number and located mainly in the infundibular nucleus.  

These results demonstrate that the infundibular nucleus plays a major role in control of GH secretion in man and that secretion of GRF appears late during fetal life; this suggests that the first stages of differentiation and development of GH producing cells in the human fetus do not depend on hypothalamic GRF secretion..  

Using antibodies developed against synthetic porcine neuropeptide Y (NPY), we have been able to localize immunoreactivity in neuronal cell bodies located exclusively in the infundibular nucleus.  

Cerebrospinal fluid contacting somatostatin perikarya of the infundibular nucleus terminate with club-like endings in the ventricular cavity.  

Radioautography showed specific binding of insulin localized to the median eminence, infundibular nucleus, and microvessels.  

Immunoreactive TRH cell bodies are found in the anterior part of the preoptic nucleus, the dorsal infundibular nucleus, the nucleus of diagonal band of Broca, and the medial part of the amygdala.  

Perikarya are located in the infundibular nucleus, and their fibres end in posterior and lateral territories of the zona externa of the Median Eminence .  

Cell bodies were present in the preoptic area, the periventricular hypothalamic zone from the level of the anterior hypothalamus to the premammillary nuclei, the infundibular nucleus, supraoptic nucleus, several septal nuclei, the nervus terminalis, and the amygdala.  

GnRH-positive perikarya were localized singly or in small groups within the infundibular nucleus and were seen grouped in large discrete clusters within the ventromedial nucleus.  

GnRH positive perikarya were localized in the lamina terminalis, infundibular nucleus and the caudal periventricular nucleus.  

A number of immunoreactive neuronal perikarya occur in the medial preoptic nucleus of the rostral hypothalamus and a few in the accessory part of paraventricular nucleus and dorsal portion of the infundibular nucleus. A few immunoreactive fibers also extend ventrocaudally to the infundibular nucleus and to the neural lobe..  

In the adult, neurons immunoreactive with anti-beta-endorphin are found in the infundibular nucleus. Their axonal fibers terminate around blood vessels in the neurovascular zone and in the pituitary stalk, or establish contacts with non-immunoreactive perikarya of the infundibular nucleus.  

A scanning (SEM) and transmission electron microscopic (TEM) study of the ventricular wall of the hypothalamus of Triturus vulgaris was performed with special regard to the intraventricular dendrite terminals of the cerebrospinal fluid (CSF) contacting neurons of the preoptic area (magnocellular and parvocellular preoptic nuclei), the infundibular lobe (anterior periventricular nucleus, infundibular nucleus), and the paraventricular organ.  

Within the hypertrophic neurons of this region, which we designate the subventricular part of the infundibular nucleus, nuclear spheroids are definitely more frequent, and they are of the large type.  

HRP-RP was also found in perikarya of parvocellular secretory neurons in the infundibular nucleus 48 h after injection of HRP into the median eminence but not after injection into the pars nervosa. This provides direct evidence that a conspicuous component of the tubero-infundibular tract is formed by axons of tuberal neurons that originate from the infundibular nucleus and pass directly into the median eminence..  

These results suggest that neurons of the infundibular nucleus can store and probably secrete peptide similar to propiocortin or fragment(s) of this molecule..  

Their perikarya are located in the infundibular nucleus. Some fibres terminate close to vessels in the median eminence, others form pericellular baskets around perikarya of non-immunoreactive neurons of the infundibular nucleus.  

In addition to the previously described system, located in the preoptic nucleus, a second system could be demonstrated in the infundibular nucleus.  

Using a antiserum specific to somatostatin and the unlabeled antibody peroxidase-antiperoxidase technique, we have found somatostatin in neurons with cell bodies in an area in the anterior hypothalamus corresponding to the infundibular nucleus.  

In Man they form four main groups localized in the medio basal hypothalamus (infundibular nucleus, post-infundibular eminence, premammillary nucleus), the preopticoterminal area, the septum (and pericommissural area), the retromammillary area and the rostral mesencephalon.  

Implantation of glass capillary tubes containing TP in the basal infundibular nucleus (IN), in the median eminence, or in the pars distalis inhibited the photoperiodically induced increase in plasma levels of luteinizing hormone (LH), as measured by radioimmunoassay, and testicular growth.  

Lesions in the basal infundibular nucleus (IN) that resulted in complete inhibition of testicular growth abolished Zugunruhe, but allowed varying degrees of fattening.  

Some of these were found in the media-basal hypothalamus in the infundibular nucleus and lateral and dorsal to it, while others were found in dorsal hypothalamus.  

The heaviest accumulations of catecholamine-containing varicosities were seen within the: anterior periventricular nucleus; dorsal hypothalamic area; bed nucleus of the inferior thalamic peduncle; doral component of the paraventricular nucleus; dorsomedial nucleus; infundibular nucleus; bed nucleus of the stria terminalis-medial division; and supraoptic nucelus.  

Estrogen was concentrated by cells in three telencephalic areas (the ventral striatum, the ventral-lateral septum and the amygdala), the anterior preoptic area, the ventral thalamus, the ventral infundibular nucleus, and in the torus semicircularis. The anterior preoptic area and the ventral infundibular nucleus contained the greatest number of labelled cells.  

Four major hormone uptake sites were identified: the anterior preoptic area, the ventral infundibular nucleus, a dorsal tegmental area of the medulla and a presumptive motor nucleus of cranial nerves IX-X.  

Photoperiodic stimulation appears to increase the numbers of apical protrusions of the cells in the ventral glandular ependyma and to cause an increase in size of the nerve cells of the basal infundibular nucleus..  

Immuno-enzyme histochemical investigations on the bovine hypothalamus showed that the infundibular nucleus contains neurons that produce either neurophysin I or a neurophysin I-like substance.  

Determinations of the label uptake at two specific times in the experiment, in the infundibular nucleus, ventromedial nucleus and optic nerve tissue in both series served as a check on the specifity of the structural protein turnover changes observed.  

In the dog, specific immunoreactive perikarya have also been found in the pars oralis tuberi, the infundibular nucleus, the premammillary region, and even the dorsomedial and ventromedial areas and the rostral mesencephalon..  


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