Fos Expression in the Rat Brain After Intraperitoneal Injection of Staphylococcus Enterotoxin B and the Effect of Vagotomy

The current study was designed to locate the neuronal activation in rat brain following intraperitoneal injection of Staphylococcus enterotoxin B (SEB) and observe the consequence of preliminary subdiaphragmatic vagotomy on SEB-induced brain Fos expression to clarify the role of the vagus nerve in sensation and transmission of abdominal SEB stimulation. The results showed that intraperitoneal SEB (1 mg/kg) induced a robust Fos expression in widespread brain areas. A significant increase of Fos immunoreactive cells were observed in the solitary tract nucleus, locus ceruleus, lateral parabrachial nucleus, ventrolateral part of central gray, medial amygdaloid nucleus, central amygdaloid nucleus, ventromedial part of thalamus, dorsomedial part of thalamus, hypothalamic paraventricular nucleus, lateral habenula, and lateral septum nucleus following SEB challenge. In hypothalamic paraventricular nucleus, in addition to the dense Fos expression in the parvocellular portion, some Fos-positive cells were also observed in the anterior magnocellular nucleus of the complex. Double immunofluorescence studies showed that these Fos-immunoreactive cells were mostly oxytocinergic. The results also showed that subdiaphragmatic vagotomy largely attenuated, but not totally abrogated, the brain Fos expression induced by abdominal administration of SEB. Our data suggest that peripheral SEB stimulation can induce activation of neurons in widespread brain areas and that the vagus plays a crucial role in transmitting the signal of abdominal immune stimulation to the brain.     

Evidence for the presence of nerve growth factor (NGF) and NGF receptors in human testis

Summary The co-localization of arginine vasopressin-and enkephalin-like immunoreactivities in nerve cells of the rat paraventricular hypothalamic nucleus and adjacent areas was investigated by the simultaneous application of immuno--galactosidase staining and the peroxidase-antiperoxidase method to sections. Arginine vasopressin-like immunoreactive cells were stained blue with immuno--galactosidase staining and enkephalin-like immunoreactive cells brown with the peroxidase-antiperoxidase method. Double-labeled cells with overlap of blue and brown immunoreaction products were identified in the anterior, medial, and lateral parvocellular parts of the paraventricular hypothalamic nucleus as well as in the previously indicated posterior magnocellular part. Other regions that contained double-labeled cells were the lateral hypothalamic area, anterior hypothalamic nucleus, area between the lateral hypothalamic area and anterior hypothalamic nucleus, suprachiasmatic nucleus, and bed nucleus of the stria terminalis, medial division, posterolateral part. These findings suggest that nerve cells with both arginine vasopressin- and enkephalin-like immunoreactivities may be more actively involved in neuroendocrine regulation and neural transmission than previously considered. They may provide a morphological basis for an increase in enkephalin-like immunoreactivity within the anterior pituitary in cases of hemorrhagic shock which is presumably accompanied by arginine vasopressin hypersecretion.Abbreviations AH anterior hypothalamic nucleus - ap anterior parvocellular part of the paraventricular hypothalamic nucleus - BSTMPL bed nucleus of the stria terminalis, medial division, posterolateral part - dp dorsal parvocellular part of the paraventricular hypothalamic nucleus - f fornix - LH lateral hypothalamic area - lp lateral paryocellular part of the paraventricular hypothalamic nuclcus - mp medial parvocellular part of the paraventricular hypothalamic nucleus - MPA medial preoptic area - pm posterior magnocellular part of the paraventricular hypothalamic nucleus - pv periventricular part of the paraventricular hypothalamic nucleus - SC suprachiasmatic nucleus - Zi zona incerta     

Expression of c-Fos gene in the rat hypothalamus upon electric painful stimulation and EHF irradiation of the skin

Studies of the activation pattern of hypothalamic cells upon electric painful stimulation have revealed an increase in the counts of c-Fos-positive cells (72.02-98.95%) predominantly of a size ranging from 10 to 50 microm2. EHF irradiation of the skin activates hypothalamic cells of the size ranging from 10 to 70 microm2 in the paraventricular, dorsomedial nuclei, and in perifonical zone of the lateral hypothalamic area. The combined action of EHF skin irradiation and electric painful stimulation leads to a decrease in the counts of cells activated in result of the painful stimulation in the anterior hypothalamic area, ventromedial nucleus, and the basal part of the lateral area. Changes in size distributions of activated cells are found in the ventromedial nucleus and the basal part of the lateral area, occur mainly through decreased counts of smaller cells (10-30 microm2) and increased counts of lager cells. The modulatory effect of EHF irradiation of the skin was found to be expressed as a reduction in hypothalamic cell activation caused by electric painful stimulation.     

Neuropeptide Y innervation of amygdaloid and hypothalamic neurons that project to the dorsal vagal complex in rat

The anatomic relationship between neuropeptide Y (NPY)-immunoreactive terminals and forebrain areas in the rat that contain neurons that project to the dorsal vagal complex (DVC) was examined. To accomplish this, the combined retrograde fluorescent tracer and immunofluorescent technique was used. Neurons projecting to the DVC within the parvocellular divisions of the paraventricular nucleus of the hypothalamus were the most heavily innervated of the regions studied. A relatively high density of NPY-immunoreactive terminals innervated regions of the arcuate, dorsomedial and lateral hypothalamic areas that contained DVC efferent cells. Neurons that projected to the DVC within the medial division of the central nucleus of the amygdala and the lateral part of the bed nucleus of the stria terminalis were also innervated by NPY immunoreactive terminals. The results suggest an important role for NPY terminals in the modulation of neurons within the amygdala and hypothalamus that directly influence visceral-autonomic functions of the dorsal vagal complex. The source and possible function of NPY within these regions is discussed.     

大鼠下丘脑内一氧化氮合酶阳性神经元的分布

用ＮＡＤＰＨ－ｄ组织化学方法观察了大白鼠下丘脑内一氧化氮合酶（ＮＤＳ）阳性神经元的分布及形态特征。结果显示：在视上核、室旁核的大细胞部、环状核、穹窿周核、下丘脑外侧区、下丘脑腹内侧核、下丘脑背内侧核、乳头体区大部分核团均可见一氧化氮合酶阳性神经元聚集成团。在视前内侧区、视前外侧区、下丘脑前区、下丘脑背侧区、下丘脑后区、室周核、室旁核小细胞部及穹窿内可见散在的一氧化氮合酶阳性神经元。室周核内可见呈阳性反应的接触脑脊液神经元的胞体及突起。一氧化氮合酶阳性神经元大多可见突起,有的突起上可见１～２级分支,并可见膨体。下丘脑大部分区域内可见阳性神经纤维。弓状核内可见许多弧形纤维连于第三脑室室管膜和正中隆起。     

Demonstration of a different localization of perikarya immunoreactive to oxytocin and vasopressin in the cat hypothalamus

Using immunohistochemical techniques, we demonstrated oxytocin (OT) and vasopressin (AVP) neurons in the cat hypothalamus. The OT immunoreactive neurons were found mainly in the paraventricular nucleus, supraoptic nucleus and dorsal accessory group located lateral to the fornix. In addition to these hypothalamic structures, the AVP immunoreactive neurons were observed in the suprachiasmatic nucleus, ventral accessory group located in the retrochiasmatic area and lateral accessory group, dorsal to the supraoptic nucleus caudally, and ventral to the medial part of the internal capsule rostrally. We further demonstrated a different localization of the OT and AVP immunoreactive neurons in the paraventricular and supraoptic nuclei.     

Immunocytochemical localization of growth hormone releasing factor (GHRF)-containing structures in the rat brain using anti-rat GHRF serum

The distribution of growth hormone releasing factor (GHRF) immunoreactive structures in the rat hypothalmus was studied after colchicine treatment with PAP immunocytochemistry in vibratome sections using an antiserum directed to rat hypothalamic GHRF. The majority of the GHRF-immunoreactive cell bodies were found in the arcuate nucleus, the medial perifornical region, and the ventral premammillary nuclei of the hypothalamus. Scattered cells were seen in the lateral basal hypothalamus, the medial and lateral portions of the ventromedial nucleus, and the dorsomedial and paraventricular nuclei. Immunoreactive fibers were observed in all the regions mentioned above. GHRF terminals were located in the central region of the median eminence. In addition, GHRF-immunoreactive neuronal processes were seen in the ventral region of the dorsomedial nucleus, the medial preoptic and suprachiasmatic regions, dorsal portion of the suprachiasmatic nucleus, bed nucleus of the stria terminals and the hypothalamic portion of the stria terminals. The localization of GHRF-immunoreactive terminals in the median eminence reinforces the view that GHRF plays a physiological role in the regulation of pituitary function. In addition, the localization of GHRF-immunoreactive structures in areas not usually considered to project to the median eminence suggest that GHRF may act as a neuromodulator or neurotransmitter.     

Autoradiographic distribution of 125I calcitonin gene-related peptide binding sites in the rat central nervous system

Using autoradiographic method and 125I-Tyro rat CGRP as a ligand, receptor binding sites were demonstrated in the rat central nervous system. Saturation studies and Scatchard analysis of CGRP-binding to slide mounted tissue sections containing primarily cerebellum showed a single class of receptors with a dissociation constant of 0.96 nM and a Bmax of 76.4 fmol/mg protein. 125I-Tyro rat CGRP binding sites were demonstrated throughout the rat central nervous system. Dense binding was observed in the telencephalon (medial prefrontal, insular and outer layers of the temporal cortex, nucleus accumbens, fundus striatum, central and inferior lateral amygdaloid nuclei, most caudal caudate putamen, organum vasculosum laminae terminalis, subfornical organ), the diencephalon (anterior hypothalamic, suprachiasmatic, arcuate, paraventricular, dorsomedial, periventricular, reuniens, rhomboid, lateral thalamic pretectalis and habenula nuclei, zona incerta), in the mesencephalon (superficial layers of the superior colliculus, central nucleus of the geniculate body, inferior colliculus, nucleus of the fifth nerve, locus coeruleus, nucleus of the mesencephalic tract, the dorsal tegmental nucleus, superior olive), in the molecular layer of the cerebellum, in the medulla oblongata (inferior olive, nucleus tractus solitarii, nucleus commissuralis, nuclei of the tenth and twelfth nerves, the prepositus hypoglossal and the gracilis nuclei, dorsomedial part of the spinal trigeminal tract), in the dorsal gray matter of the spinal cord (laminae I-VI) and the confines of the central canal. Moderate receptor densities were found in the septal area, the "head" of the anterior caudate nucleus, medial amygdaloid and bed nucleus of the stria terminalis, the pyramidal layers of the hippocampus and dentate gyri, medial preoptic area, ventromedial nucleus, lateral hypothalamic and ventrolateral thalamic area, central gray, reticular part of the substantia nigra, parvocellular reticular nucleus. Purkinje cell layer of the cerebellum, nucleus of the spinal trigeminal tract and gracile fasciculus of the spinal cord. The discrete distribution of CGRP-like binding sites in a variety of sensory systems of the brain and spinal cord as well as in thalamic and hypothalamic areas suggests a widespread involvement of CGRP in a variety of brain functions.     

Distribution of oxytocin and vasopressin neurons in the diencephalon of the Japanese horseshoe bat, Rhinolophus ferrumequinum. An immunohistochemical study.

The distribution of oxytocin (OXT) and vasopressin (VP) neurons in the diencephalon of the hibernating Japanese horseshoe bat, Rhinolophus ferrumequinum, was immunohistochemically investigated by the avidin-biotin complex method. Magnocellular OXT and VP neurons were localized mainly in the paraventricular nucleus and the supraoptic nucleus. In addition to these main nuclei, both kinds of magnocellular neurons were also found in the periventricular nucleus, perifornical area and lateral hypothalamic area. Extensively distributed parvocellular neurons containing only VP were observed in the rostral and middle portions of the suprachiasmatic nucleus. The size of OXT and VP magnocellular neurons was almost equal in the paraventricular and ventromedial supraoptic nuclei, whereas VP neurons were significantly larger than OXT neurons in the dorsolateral supraoptic nucleus. The OXT and VP cells in the ventral supraoptic nucleus showed a distinctive elliptical shape. Both OXT and VP fibers were distributed in the lateral habenular nucleus, stria medullaris thalami, lateral preoptic area, stria terminalis, and medial and supracapsular part of the bed nucleus of the stria terminalis. Moreover, OXT fibers were found in the substantia nigra, and VP fibers were noted in the nucleus reunions and the paraventricular nucleus of the thalamus.     

Thyrotropin-releasing hormone (TRH)-immunoreactive structures in the brain of the domestic mallard

Summary The distribution of immunoreactive thyrotropin-releasing hormone (TRH) in the central nervous system of the domestic mallard was studied by means of the peroxidase-antiperoxidase technique. After colchicine pretreatment, the highest number of TRH-immunoreactive perikarya was found in the parvocellular subdivision of the paraventricular nucleus and in the preoptic region; a smaller number of immunostained perikarya was observed in the lateral hypothalamic area and in the posterior medial hypothalamic nucleus. TRH-immunoreactive nerve fibers were detected throughout the hypothalamus, forming a dense network in the periventricular area, paraventricular nucleus, preoptic-suprachiasmatic region, and baso-lateral hypothalamic area. TRH-containing nerve fibers and terminals occurred in the organon vasculosum of the lamina terminalis and in the external zone of the median eminence in juxtaposition with hypophyseal portal vessels. Scattered fibers were also seen in the internal zone of the median eminence and in the rostral portion of the neural lobe. Numerous TRH-immunoreactive fibers were detected in extra-hypothalamic brain regions: the highest number of immunoreactive nerve fibers was found in the lateral septum, nucleus accumbens, olfactory tubercle, and parolfactory lobe. Moderate numbers of fibers were located in the basal forebrain, dorsomedial thalamic nuclei, hippocampus, interpeduncular nucleus, and the central gray of the mesencephalon. The present findings suggest that TRH may be involved in hypophysiotropic regulatory mechanisms and, in addition, may also act as neuromodulator or neurotransmitter in other regions of the avian brain.     

c-Fos expression in the central nervous system elicited by phrenic nerve stimulation.

Phrenic nerve afferents (PNa) have been shown to activate neurons in the spinal cord, brain stem, and forebrain regions. The c-Fos technique has been widely used as a method to identify neuronal regions activated by afferent stimulation. This technique was used to identify central neural areas activated by PNa. The right phrenic nerve of urethane-anesthetized rats was stimulated in the thorax. The spinal cord and brain were sectioned and stained for c-Fos expression. Labeled neurons were found in the dorsal horn laminae I and II of the C3-C5 spinal cord ipsilateral to the site of PNa stimulation. c-Fos-labeled neurons were found bilaterally in the medial subnuclei of the nucleus of the solitary tract, rostral ventral respiratory group, and ventrolateral medullary reticular formation. c-Fos-labeled neurons were found bilaterally in the paraventricular and supraoptic hypothalamic nuclei, in the paraventricular thalamic nucleus, and in the central nucleus of the amygdala. The presence of c-Fos suggests that these neurons are involved in PNa information processing and a component of the central mechanisms regulating respiratory function.     

Pattern of afferents to the lateral septum in the guinea pig

Summary The septal region represents an important telencephalic center integrating neuronal activity of cortical areas with autonomous processes. To support the functional analysis of this brain area in the guinea pig, the afferent connections to the lateral septal nucleus were investigated by the use of iontophoretically applied horseradish peroxidase (HRP). Retrogradely labeled perikarya were located in telencephalic, diencephalic, mesencephalic and metencephalic sites. The subnuclei of the lateral septum (pars dorsalis, intermedia, ventralis, posterior) receive afferents from the (i) medial septal nucleus, diagonal band of Broca (pars horizontalis and pars ventralis), and the principal nucleus of the stria terminalis, the hippocampus, and amygdala (nucleus medialis); (ii) the medial habenular nucleus, and the para- (peri-) ventricular, parataenial and reuniens nuclei of the thalamus; the anterior, lateral and posterior hypothalamic areas in particular, the medial and lateral preoptic, suprachiasmatic, periventricular, paraventricular, arcuate, premammillary, and supramammillary nuclei; (iii) the periaquaeductal grey, ventral tegmental area, nucleus interfascicularis, nucleus reticularis linearis, central linear nucleus, interpeduncular nucleus; (iv) dorsal and medial raphe complex, and locus coeruleus. Each subnucleus of the lateral septum displays an individual, differing pattern of afferents from the above-described regions. Based on a double-labeling method, the vasopressinergic and serotonergic afferents to the lateral septum were found to originate in the nucleus paraventricularis hypothalami and the raphe nuclei, respectively.Abbreviations ARC arcuate nucleus - BNST bed nucleus of the stria terminalis - CL central linear nucleus - DBBh diagonal band of Broca (pars horizontalis) - DBBv diagonal band of Broca (pars ventralis) - DR dorsal raphe nucleus - HC hippocampus - IF interfascicular nucleus - IP interpeduncular nucleus - LC locus coeruleus - LDT laterodorsal tegmental nucleus - LHA lateral hypothalamic area - LPO lateral preoptic area - LSN lateral septal nucleus - MA medial amygdaloid nucleus - MH medial habenular nucleus - MPO medial preoptic region - MR medial raphe nucleus - MSN medial septal nucleus - PAG periaquaeductal grey - PEN periventricular nucleus - PHA posterior hypothalamic area - PMd premammillary region (pars dorsalis) - PMv premammillary region (pars ventralis) - PT parataenial nucleus - PVN paraventricular hypothalamic nucleus - PVT paraventricular thalamic nucleus - RE nucl. reuniens - RL nucl. reticularis linearis - SCN suprachiasmatic nucleus - SMl supramammillary region (pars lateralis) - SMm supramammillary region (pars medialis) - SUB subiculum - TS triangular septal nucleus - VTA ventral tegmental area - ac anterior commissure - bc brachium conjunctivum - bp brachium pontis - cc corpus callosum - fr fasciculus retroflexus - fx fornix - ml medial lemniscus - mlf fasciculus longitudinalis medialis - mp mammillary peduncle - mt mammillary tract - oc optic chiasm - on optic nerve - pc posterior commissure - pt pyramidal tract - sm stria medullaris - st stria terminalis - vhc ventral hippocampal commissure Supported by the Deutsche Forschungsgemeinschaft (Nu 36/2-1)     

寒冷对大鼠下丘脑核团癌基因c-fos及垂体ACTH细胞表达的变化

本实验用寒冷刺激大鼠,观察垂体ＡＣＴＨ细胞及下丘脑核团ｃ－ｆｏｓ癌基因表达蛋白出现的变化。发现寒冷能促使垂体前叶ＡＣＴＨ细胞数目增多,体积胀大,且具有粗大突起伸到扩张的血窦旁。在视交叉腹外侧的视上核（ＳＯ）神经元及视交叉上核（Ｓｃｈ）周围部神经元皆出现ｃ－ｆｏｓ强阳性反应。第三脑室侧壁室管膜上皮及少数室周核（ｐｅ）神经元为ｃ－ｆｏｓ阳性。视前内侧区（ＭＰＡ）可见分散的阳性神经元。位于室旁核内的外侧,出现ｃ－ｆｏｓ反应较浅的小神经元。本文最后探讨有关ＡＣＴＨ释放的调节。     

Distribution of somatostatinlike immunoreactivity in the brain of the little brown bat (Myotis lucifugus)

The distribution of somatostatinlike immunoreactive (SLI) perikarya, axons, and terminals was mapped in subcortical areas of the brain of the little brown bat, Myotis lucifugus, using light microscopic immunocytochemistry. A preponderance of immunoreactivity was localized in reticular, limbic, and hypothalamic areas including: 1) in the forebrain: the bed nucleus of the stria terminalis; lateral preoptic, dorsal, anterior, lateral and posterior hypothalamic areas; amygdaloid, periventricular, arcuate, supraoptic, suprachiasmatic, ventromedial, dorsomedial, paraventricular, lateral and medial mammillary, and lateral septal nuclei; the nucleus of the diagonal band of Broca and nucleus accumbens septi; 2) in the midbrain: the periaqueductal gray, interpeduncular, dorsal and ventral tegmental, pretectal, and Edinger-Westphal nuclei; and 3) in the hindbrain: the superior central and parabrachial nuclei, nucleus incertus, locus coeruleus, and nucleus reticularis gigantocellularis. Other areas containing SLI included the striatum (caudate nucleus and putamen), zona incerta, infundibulum, supramammillary and premammillary nuclei, medial and dorsal lateral geniculate nuclei, entopeduncular nucleus, lateral habenular nucleus, central medial thalamic nucleus, central tegmental field, linear and dorsal raphe nuclei, nucleus of Darkschewitsch, superior and inferior colliculi, nucleus ruber, substantia nigra, mesencephalic nucleus of V, inferior olivary nucleus, inferior central nucleus, nucleus prepositus, and deep cerebellar nuclei. While these results were similar in some respects to those previously reported in rodents, they also provided interesting contrasts.     

Neuropeptide FF2 receptor distribution in the human brain. An immunohistochemical study

Human neuropeptide FF2 (hFF2) receptor has been postulated to mediate central autonomic regulation by virtue of its ability to bind with high affinity to many amidated neuropeptides. In the present immunohistochemical study, we identified hFF2 positive neurons in the forebrain and medulla oblongata of individuals, who died suddenly of mechanical trauma or hypothermia. Morphologically, these neurons demonstrated features identified with both projection neurons and interneurons. In the forebrain, the highest density of hFF2 expressing neurons was observed in the anterior amygdaloid area and dorsomedial hypothalamic nucleus, especially in its caudal part. A lesser density of hFF2 neurons was identified in the ventromedial hypothalamic nucleus, lateral and posterior hypothalamic areas whereas few cells were visualized in the paraventricular hypothalamic nucleus, perifornical nucleus, horizontal limb of the diagonal band, ventral division of the bed nucleus of the stria terminalis, nucleus basalis of Meynert and ventral tegmental area. In the medulla, significant numbers of hFF2 neurons were observed in the dorsal motor nucleus of vagus and to a lesser extent in the area of catecholaminergic cell groups, A1/C1. These data provide first immunohistochemical evidence of hFF2 localization in the human brain, which is consistent with that reported for tissue distribution of FF2 mRNA and FF2 binding sites within the brain of a variety of mammalian species. The distribution of hFF2 may help in identifying the role of amidated neuropeptides in the human brain within the context of central autonomic and neuroendocrine regulation.     

Electron microscopic analysis of tyrosine hydroxylase, dopamine-beta-hydroxylase and phenylethanolamine-N-methyltransferase immunoreactive innervation of the hypothalamic paraventricular nucleus in the rat

The catecholaminergic innervation of the hypothalamic paraventricular nucleus (PVN) of the rat was studied by preembedding immunocytochemical methods utilizing specific antibodies which were generated against catecholamine synthesizing enzymes. Phenylethanolamine-N-methyltransferase (PNMT)-immunoreactive terminals contained 80-120 nm dense core granules and 30-50 nm clear synaptic vesicles. The labeled boutons terminated on cell bodies and dendrites of both parvo- and magnocellular neurons of PVN via asymmetric synapses. The parvocellular subnuclei received a more intense adrenergic innervation than did the magnocellular regions of the nucleus. Dopamine-beta-hydroxylase (DBH)-immunopositive axons were most numerous in the periventricular zone and the medial parvocellular subnucleus of PVN. Labeled terminal boutons contained 70-100 nm dense granules and clusters of spherical, electron lucent vesicles. Dendrites, perikarya and spinous structures of paraventricular neurons were observed to be the postsynaptic targets of DBH axon terminals. These asymmetric synapses frequently exhibited subsynaptic dense bodies. Paraventricular neurons did not demonstrate either PNMT or DBH immunoreactivity. The fibers present within the nucleus which contained these enzymes are considered to represent extrinsic afferent connections to neurons of the PVN. Tyrosine hydroxylase (TH)-immunoreactivity was found both in neurons and neuronal processes within the PVN. In TH-cells, the immunolabel was associated with rough endoplasmic reticulum, free ribosomes and 70-120 nm dense granules. Occasionally, nematosome-like bodies and cilia were observed in the TH-perikarya. Unlabeled axons established en passant and bouton terminaux type synapses with these TH-immunopositive cells. TH-immunoreactive axons terminated on cell bodies as well as somatic and dendritic spines of paraventricular parvocellular neurons. TH-containing axons were observed to deeply invaginate into both dendrites and perikarya of magnocellular neurons. These observations provide ultrastructural evidence for the participation of central catecholaminergic neuronal systems in the regulation of the different neuronal and neuroendocrine functions which have been related to hypothalamic paraventricular neurons.     

刺激大鼠穹窿下器官诱发饮水和脑内c—fos表达的胆碱能机制

实验以饮水行为脑内c-fos表达为指标,,观察刺激大鼠穹窿下器官（SFO）的效应,结果显示,刺激SFO能诱发明显的饮水行为,与此同时,前脑8个部位（终板血管器官,正中视前核,室旁核,视上核,下丘脑外侧区,穹窿周核背侧区,丘脑联合核和无名质）和后脑3个部位（最后区,孤束核和壁旁外侧核）的Fos蛋白表达明显增强,免疫组化双重染色结果显示,刺激SFO能诱导视上核和室旁核中部分神经元呈Fos蛋白和加压素共同表达。脑室注射阿托品能部分阻断刺激SFO诱发的饮水行为,脑内上述各部位所诱导的Fos蛋白表达也明显减弱,以上结果提示,M胆碱能机制参与 刺激SFO诱发的饮水行为和脑内Fos蛋白的表达。     

Localization of luteinizing hormone-releasing hormone in the forebrain of the pig

The distribution of luteinizing hormone-releasing hormone (LHRH)-immunostained perikarya and processes was examined in the forebrains of six sexually mature female pigs by use of indirect biotin-avidin horseradish peroxidase immunocytochemistry. Two primary antisera (Drs. Y.F. Chen and V.D. Ramirez CRR11B73 and Miles-Yeda UZ-4) yielded positive staining. Adjacent sections treated either primary antiserum preabsorbed with LHRH or with normal rabbit serum substituted for primary antiserum lacked positive staining. The greatest proportion of LHRH-immunostained perikarya were found in the medial preoptic area adjacent to the organum vasculosum of the lamina terminalis. The LHRH-immunostained perikarya were also scattered rostrally in the diagonal band of Broca, and within the lateral hypothalamic area, paraventricular nucleus, periventricular zone, suprachiasmatic nucleus, and medial basal hypothalamus. LHRH-immunostained processes, which extended from the medial preoptic area, coursed either along the ventral surface to the median eminence or medially and ventrally along the third ventricular wall ventrally to the median eminence and caudally to the level of the mammillary bodies. Extrahypothalamic processes were located adjacent to the lateral ventricular floor and the third ventricle from the lateral septal area (stria terminalis) to the level of the habenular nucleus. LHRH-immunostained neurons were unipolar, bipolar, and multipolar. Close associations between individual LHRH-immunostained neurons were observed.     

Role of the hypothalamus in regulating liver circulation

In acute experiments on nembutal anesthetized dogs stimulation of anterior hypothalamus elicited changes in the hepatic artery blood flow, which followed those of arterial pressure; the vascular resistance remaining unchanged. The stimulation of medial and posterior hypothalamus led to decrease in flow and increase in the resistance of the hepatic artery. In most cases of hypothalamic stimulation the portal blood flow diminished, portal pressure and vascular resistance increased. The opposite reactions were observed during stimulation of sympathoinhibitory area, paraventricular and lateral hypothalamic nuclei. The conclusion is made that the hypothalamus participates in integrative and differential control of the hepatic circulation.     

Morphology of neuroglia in the hypothalamus of the opossum (Didelphis virginiana), armadillo (Dasypus novemcinctus mexicanus) and cat (Felis domestica)

The hypothalamus of the opossum (Didelphis virginiana), the armadillo (Dasypus novemcinctus mexicanus), and the cat (Felis domestica) was studied using Del Rio Hortega's silver carbonate technique, as modified by Scharenberg ('60). This technique demonstrates astrocytes, oligodendroglia, and neuronal perikarya, but does not impregnate microglia. The morphology of macroglia was observed in ten comparable nuclei in each of the three species. The subpial and subependymal areas were also examined. Astrocytes display more cell body angularity and have more processes in most hypothalamic regions of the cat when compared to similar regions of the opossum and armadillo. In the anterior hypothalamic nucleus, the ventromedial and the dorsomedial hypothalamic nuclei, and the medial mammillary nucleus of all three species, astrocytes send processes to neurons, but neuronal and astrocytic perikarya are usually not directly contiguous. However, oligodendrocytes in a perisomatic position on neurons are a consistent feature in these nuclei. A closer relationship appears to exist between astrocytes and neurons in the neurosecretory nuclei. In the supraoptic nucleus and paraventricular nucleus of all three species a basket-like structure, designated a ?pericellular envelope”? was observed surrounding neuronal perikarya. This structure is composed of astrocytic and oligodendroglial cell bodies and processes, and is most highly developed in the cat. A dense astrocytic plexus was observed in the suprachiasmatic nucleus of the cat, and in the comparable nuclei of the armadillo and opossum. The most prominent macroglial cell type of the lateral hypothalamic and lateral mammillary nuclei of all three species is the interfascicular oligodendrocyte. The posterior hypothalamic nucleus of each species has many perisomatic oligodendrocytes, and in the armadillo and cat astrocytes are closely related to the larger neurons. A subpial plexus, consisting of a palisade of small glial cells with many processes, is present in the hypothalamus of the three species. Ependymal cells have long projecting processes throughout the length of the third ventricle in the armadillo hypothalamus, but such processes are only apparent in the region of the infundibular nucleus and median eminence in the opossum and cat.