Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Direct projections from the A1/C1 catecholaminergic cell group in the caudal ventrolateral medulla oblongata to neurons containing vasopressin (VP) in the supraoptic nucleus (SON) were studied electron microscopically by a double-labeling technique which combines anterograde tracing after injection of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) into the A1/C1 cell group with VP immunocytochemistry. WGA-HRP-labeled axon terminals originating from neurons in the A1/C1 cell group were found to make synaptic contacts with VP-immunoreactive cell bodies and dendrites in the SON, most often forming axo-dendritic synapses. This indicates that VP-containing neurosecretory neurons in the SON receive monosynaptic catecholaminergic input from the A1/C1 cell group.
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PMID:Ultrastructural studies of medullary synaptic inputs to vasopressin-immunoreactive neurons in the supraoptic nucleus of the rat hypothalamus. 128 40

A study was made of portions of the gastrointestinal tract including the stomach, duodenum, jejunum, ileum, colon and rectum, and the hypothalamus of hedgehogs using the peroxidase-antiperoxidase (PAP) method incubating paraffin embedded sections of 6-7 microns thickness in an anti-arginine-vasopressin serum at a dilution of 1:1000. Vasopressin-like immunoreactivity is present in cells of the epithelial layer of the intestinal mucosa ranging from the stomach to the rectum. In the stomach the numbers of these cells are very small although they increase in the small intestine. However, in the different portions of this latter organ no significant differences can be found. Both, in colon and rectum there are cells with vasopressin-like immunoreactive material although at higher concentrations than in the rest of the gastrointestinal (GI) tract. Immunoreactive material is present throughout the epithelial layer of the mucosa and in general the cells of the mucosa are of the open kind. Using the same antiserum and at similar dilution, both cells and nerve fibres containing vasopressin-like immunoreactivity were observed in hypothalamic sections of this animal species and were used as positive controls. It is concluded that in the gastrointestinal (GI) tract of the hedgehog there is a population of epithelial cells that contain a immunoreactivity vasopressin-like-peptide (referred to as vasopressin-like peptide (AV-LP) whose numbers increase in the distal sense.
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PMID:Immunocytochemical study of vasopressin-like immunoreactive material in the gastrointestinal tract of the hedgehog Erinanceus europeus. 138 57

In the neurosecretory nerve endings of the neurohypophysis depolarization-induced exocytosis is followed by endocytosis of vacuole-like structures with diameter similar to that of neurosecretory granules. However, it remains unknown whether the membrane of the endocytotic vacuoles is comprised primarily of retrieved secretory granule membrane, plasma membrane or of a mixture of the granule and plasma membrane. In the present paper membrane retrieval following depolarization-induced exocytosis has been studied in isolated neurosecretory nerve endings from the rat neurohypophysis. The origin of the retrieved membrane was assessed by pre-labeling the plasma membrane with an antibody against neural cell adhesion molecule, a plasma membrane specific protein. Horseradish peroxidase was used as an index of fluid endocytosis and secretion of vasopressin was measured by radioimmunoassay. Following potassium-induced depolarization, endocytotic vacuoles showed labeling with the fluid phase marker horseradish peroxidase but never showed significant neural cell adhesion molecule labeling. The time-course of endocytosis following closely that of exocytosis as endocytotic vacuoles labeled with horseradish peroxidase were only observed when the fluid phase marker was present in the extracellular medium during the period of evoked exocytosis. Our results are consistent with a model in which in neurosecretory nerve endings, after transient exocytotic fusion of the granule membrane with the plasma membrane, the granule membrane is rapidly and selectively retrieved into the nerve endings in the form of vacuoles similar in size to that of the neurosecretory granules.
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PMID:Membrane retrieval following exocytosis in isolated neurosecretory nerve endings. 140 46

Using the peroxidase-antiperoxidase immunocytochemical technique, a morphometric study of the magnocellular neurons of the Paraventricular nucleus of the rat hypothalamus, reactive to specific anti-vasopressin rabbit serum, was made. Following systemic and chronic administration of met-enkephalin the number of immunoreactive neurons was higher, especially in females. Additionally, in the females, it was possible to observe an increase in the immunoreactivity and the presence of well-stained fibres. These findings suggest, especially in females, a blockage in the release of vasopressin, facilitating its immunocytochemical visualization.
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PMID:Sex-specific response of the vasopressin-reacting neurons of the paraventricular nucleus of the rat hypothalamus following chronic administration of met-enkephalin. 145 94

The noradrenergic innervation of vasopressin (VP)-containing neurons in the supraoptic nucleus (SON) of the rat hypothalamus was studied electron microscopically by using double-labeling immunocytochemistry combining the pre-embedding peroxidase-anti-peroxidase method with post-embedding immunocolloidal gold staining. Noradrenaline-like immunoreactive axon terminals were found to make synaptic contacts with neurophysin II-like immunoreactive neurons in the SON. This provides morphological evidence for noradrenergic control of neuronal activity of VP-containing neurons at the SON level.
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PMID:Noradrenergic innervation of vasopressin-containing neurons in the rat hypothalamic supraoptic nucleus. 150 81

Many hormones and drugs exert their effects on cells by increasing cytosolic Ca2+ (Cai2+) and activating protein kinase C (PKC). Each of these actions results in cholestasis in the isolated perfused rat liver, but the responsible mechanisms are unclear. We used isolated rat hepatocyte couplets to observe the direct effects of increased Cai2+ and PKC activation on permeability of the hepatocyte tight junction and canalicular volume, two possible determinants of hepatocyte bile secretion. Couplets were stimulated with the Ca2+ agonist vasopressin (10(-8) M) in the absence and presence of the Ca2+ influx antagonist Ni2+ (5 x 10(-3) M) or with the PKC activator phorbol dibutyrate (10(-6) M). Cai2+ was determined by ratio microspectrofluorometry of indo-1, permeability of the couplet tight junctions was assessed by exclusion of horseradish peroxidase from the canalicular space, and changes in canalicular volume over time were measured directly by optical planimetry. Canalicular volume increased by 1.6 +/- 2.5%/min (mean +/- SD) under basal conditions. In response to vasopressin, there was a rapid 15-fold increase in Cai2+, followed first by an increase in paracellular permeability, then by canalicular collapse (15.9 +/- 5.9%/min). Pretreatment with Ni2+ markedly decreased the vasopressin-induced increase in Cai2+ and abolished both the increase in paracellular permeability and the canalicular collapse. Phorbol dibutyrate also increased paracellular permeability but resulted in neither increased Cai2+ nor canalicular collapse. The PKC inhibitor H-7 reversed the effects of both vasopressin and phorbol dibutyrate on tight junction permeability. Bile secretory pressure, measured in isolated perfused rat liver preparations, was acutely increased by vasopressin, but the increase was augmented rather than inhibited by Ni2+.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hormonal regulation of paracellular permeability in isolated rat hepatocyte couplets. 161 38

The subfornical organ, along with other regions of the lamina terminalis, may contain osmoreceptors and is likely to be a site of action of blood-borne angiotensin II. The neural pathways by which these stimuli lead to vasopressin secretion, have been suggested to extend from the subfornical organ to hypothalamic sites of vasopressin production either directly or via synapses in an intervening nucleus such as the median preoptic nucleus. In the present study, cholera toxin conjugated to horseradish peroxidase (CT/HRP) or colloidal gold (CT/Au) has been injected, respectively, into the subfornical organ and supraoptic nucleus of the same animal. The anterograde and retrograde transport of the toxin from these two sites has made possible the identification, at the ultrastructural level, of a synapse in the median preoptic nucleus interposed in the pathway between the subfornical organ and the supraoptic nucleus. Moreover, the presence of retrogradely transported CT/HRP and CT/Au in the same neurone in the median preoptic nucleus indicates that some neurones in this nucleus have axons with collateral branches to both the subfornical organ and supraoptic nucleus. Either or both of these pathways may transmit information related to the tonicity of the blood or circulating levels of angiotensin II to sites in the hypothalamus.
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PMID:Projections from the subfornical organ to the supraoptic nucleus in the rat: ultrastructural identification of an interposed synapse in the median preoptic nucleus using a combination of neuronal tracers. 165 10

The suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) are retinorecipient structures that play important roles in the expression of circadian rhythmicity. We examined these two structures in a diurnal ground squirrel, Spermophilus lateralis, using immunohistochemical techniques, and cholera toxin-bound horseradish peroxidase. A number of immunoreactive substances are distributed within the ground squirrel SCN in a pattern similar to that reported in many other mammals. These include vasopressin, vasoactive intestinal polypeptide, serotonin, neuropeptide Y (NPY), and glial fibrillary acidic protein. The squirrel SCN differs from that of most other species examined to date in two respects. First, a dense cluster of cells containing immunoreactive L-enkephalin (L-ENK-IR) is observed in the center of the SCN. Second, there is a contralateral, but no ipsilateral, projection from the retina to the SCN. In the lateral geniculate region there is a substantial region that contains NPY-immunoreactive cells and receives a bilateral retinal projection. This region is assumed to be homologous with the IGL described in other mammals. Cells containing L-ENK-IR are distributed throughout the LGN in groups that overlap, but which have a distinctly different distribution than the more extensive groups of NPY-IR cells.
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PMID:Immunocytochemical characterization of the suprachiasmatic nucleus and the intergeniculate leaflet in the diurnal ground squirrel, Spermophilus lateralis. 172 27

Opioid peptide- as well as vasopressin-containing neurons synapse on gonadotropin releasing hormone neurons in juvenile macaques. In this study we performed double-label immunostaining for opioid and vasopressin neurons in the paraventricular and supraoptic nuclei in order to assess their interrelationships. Neuroendocrine neurons in the hypothalamus were prelabeled by microinjection of electron-dense retrograde tracer into the median eminence, and were easily identified in frontal Vibratome sections. Sections through the paraventricular and supraoptic nuclei were immunostained for vasopressin with the peroxidase-antiperoxidase technique, and for opioids using the indirect immunogold method. By light microscopy, opioid-immunoreactive inputs appeared to innervate an average of 39% of the vasopressin neurons in the paraventricular nucleus and 33% in the supraoptic nucleus, and were more prevalent anteriorly. Clusters of opioid afferents formed cup-like calices around major processes of many vasopressin neurons, especially in the paraventricular nucleus. Electron microscopy revealed that these groups of opioid axon terminals made frequent symmetrical and fewer asymmetrical synapses on both neuroendocrine and non-neuroendocrine vasopressinergic cell bodies and dendrites. Our study did not reveal vasopressin-opioid synapses in these hypothalamic nuclei, but this does not preclude the possibility of their existence elsewhere. These results indicate that opioid afferents modulate vasopressin neuronal activity in the monkey paraventricular and supraoptic nuclei. Previous results have suggested that corticotropin releasing hormone acts via vasopressinergic neurons to stimulate opioid neuronal activity and to inhibit gonadotropin releasing hormone release. Taken together, the data suggest that stressful stimuli could initiate a series of neuropeptidergic interactions which ultimately alter pulsatile gonadotropin releasing hormone secretion and thus gonadotropin secretion in primates.
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PMID:Opioid synapses on vasopressin neurons in the paraventricular and supraoptic nuclei of juvenile monkeys. 177 44

By means of the peroxidase-antiperoxidase technique a comparative immunocytochemical study of the distribution of the vasotocin- and vasopressin-reacting system in the chicken and rat hypothalamus was carried out. In both species it is possible to distinguish, on the basis of their topographical location, three different comparable populations: The first one is situated very close to the pial surface and the optic chiasma (L1 and L2 groups in the chicken and the supraoptic nucleus in the rat). The second one is located near to the third ventricle and corresponds to the suprachiasmatic nucleus of both species and the periventricular groups of the chicken (P1, P2, and P3 groups) and the periventricular subdivision of the paraventricular nucleus of the rat. The third one is situated between the two previous populations and consists of small clusters of reacting neurons (L3 and L5 groups in the chicken and the nucleus circularis and fornicalis in the rat) and to a large cluster of reacting neurons (L4 group in the chicken and the magnocellular part of the paraventricular nucleus in rat). In the median eminence of the chicken the immunoreactive axons were located in the internal zone and the anterior part of the external zone. However in the rat, the reaction was exclusively located in the internal zone.
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PMID:A comparative analysis of the vasotocin and vasopressin systems in the chicken and rat hypothalamus. An immunocytochemical study. 181 Oct 16


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