Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bilateral electrolytic lesions and unilateral tracer injections were performed in lactating rats in order to study the participation of the mesencephalic lateral tegmentum in the milk-ejection reflex. The release of oxytocin was detected as a rise in intramammary pressure during each milk ejection. In animals with lesions, the lateral part of the deep grey layers of the superior colliculus, the intercollicular area and the rostromedial portion of the external nucleus of the inferior colliculus were destroyed. The mesencephalic lateral tegmentum of animals in which the milk-ejection reflex was blocked sustained a larger damage than in rats where the frequency of the milk-ejection response was only slowed down. Solutions of True Blue, horseradish peroxidase or horseradish peroxidase coupled to wheat germ agglutinin were injected in the mesencephalic lateral tegmentum of rats with and without lesions. Retrogradely labelled cells were found in several nuclei of the somatosensory pathways: the principal sensory and spinal parts of the trigeminal complex, the cuneate and gracile nuclei, the lateral cervical nucleus and the nucleus proprius of the spinal cord. Labelled cells were also found in the ventral nucleus of the lateral lemniscus, the ventral parabrachial nucleus, the gigantocellular reticular nucleus, the lateral nucleus of the substantia nigra, the prerubral nucleus of the thalamus, the hypothalamic ventromedial nucleus, the zona incerta and in the anterior and lateral hypothalamic areas. Labelled fibres and "terminal-like" labelling were found in the anterior pretectal area, in the thalamic parafascicular nucleus, in the posterior nucleus and the ventroposterior complex, in the zona incerta and in the fields of Forel, but none were observed in the supraoptic or paraventricular nuclei. Injections made in the area of the lateral cervical nucleus and in the cuneate and gracile nuclei labelled fibres and "terminal-like" fields in the external nucleus of the inferior colliculus, the intercollicular area, the deep grey layers of the superior colliculus and in the mesencephalic lateral tegmentum. After injections in the posterior nucleus and ventroposterior complex of the thalamus, retrogradely labelled cells were found in the lateral tegmentum, the intercollicular area and the external nucleus of the inferior colliculus. These results indicate that bilateral lesioning of the mesencephalic lateral tegmentum, which disrupts the milk-ejection response, could damage somatosensory projections originating from the dorsal horn of the spinal cord, the lateral cervical nucleus, the dorsal column nuclei and the sensory and spinal trigeminal nuclei.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Somatosensory systems and the milk-ejection reflex in the rat. I. Lesions of the mesencephalic lateral tegmentum disrupt the reflex and damage mesencephalic somatosensory connections. 384 Feb 36

The presence of oxytocin in ovarian tissue was examined immunocytochemically. Bovine antral follicles and corpora lutea were fixed with glutaraldehyde, picric acid and acetic acid fixative and immuno-stained by the indirect peroxidase-antiperoxidase (PAP) technique. Immunoreactive oxytocin was demonstrated in the granulosa cells of small and large follicles, in the granulosa-lutein cells of the young corpus luteum and in the large luteal cells of the mature corpus luteum. The regressing corpus luteum was not stainable. It is discussed that these findings additionally support the view that oxytocin is actually synthesized in ovarian tissues.
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PMID:Immunocytochemical demonstration of oxytocin in bovine ovarian tissues. 389 91

To study the morphological substrate for interaction between two chemically distinct neuronal types, two double ultrastructural immunolabeling strategies were employed. In the first, two different electron-dense markers were used to examine simultaneously two different neurotransmitter-related antigens in the hypothalamic supraoptic nucleus in the same thin section. Results obtained with the first method were confirmed with a second approach based on postembedding immunostaining of alternate serial thin sections with different antisera. Antiserum against glutamate decarboxylase, the enzyme responsible for the synthesis of the inhibitory amino acid transmitter gamma-aminobutyric acid (GABA), or antisera against GABA, was used to localize immunoreactive axons in the hypothalamic supraoptic nucleus. With light microscopy, glutamate decarboxylase- and GABA-immunoreactive axon terminals immunostained with peroxidase were found arborizing throughout all areas of the nucleus; terminal boutons were found adjacent to unlabeled somata within the nucleus. Cells containing immunoreactive oxytocin, vasopressin, and neurophysin were localized with peroxidase. Glutamate decarboxylase-immunoreactive axons stained with peroxidase prior to embedding in plastic were demonstrated to contact neurons which contained vesicles immunostained with neurophysin antiserum by a post-embedding immunocytochemical procedure which used immunoglobulins or protein A adsorbed to colloidal gold as a second ultrastructural marker. Quantitative evaluation of post-embedding staining with colloidal gold using a neurophysin primary antiserum indicated a specific antigen localization in neurosecretory vesicles. A critical factor in this double-labeling paradigm was that immunological reagents used in the second series did not cross-react with those used in the first series, regardless of the species of origin of antisera. To provide further verification of GABAergic synapses on neurophysin-containing neurons, alternate serial ultrathin sections were stained with colloidal gold using antisera against either neurophysin or GABA; boutons immunoreactive for GABA made synaptic contact with supraoptic neurons containing neurophysin immunoreactivity. Converging results obtained with these two procedures indicate that GABAergic axons synapse directly on neurons containing oxytocin or vasopressin in the rat hypothalamic supraoptic nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Dual ultrastructural localization of two neurotransmitter-related antigens: colloidal gold-labeled neurophysin-immunoreactive supraoptic neurons receive peroxidase-labeled glutamate decarboxylase- or gold-labeled GABA-immunoreactive synapses. 390 66

The distribution and the cytomorphology of neurophysin- and oxytocin-producing cells of the classic neurosecretory system of the rabbit were investigated at light microscopic level using the peroxidase-antiperoxidase (PAP) technique. Our results show that the neurons are distributed not only in the paraventricular and supraoptic nuclei, but as constituents of the suprachiasmatic nucleus and different cell clusters in the diencephalon they have a broader distribution than hitherto has been assumed. The light microscopic analysis of the exohypothalamic hypothalamo-rhombencephalic pathway shows that its fibres are closely related to neurons of the nucleus of the tractus solitarii and the dorsal motor nucleus of vagus. Following light microscopic observations suggesting that these fibres terminate on neurons in these nuclei, an immuno-electron microscopic study was undertaken. Using the pre-embedding technique, specific reaction products were observed indicating both neurophysin and oxytocin in axo-dendritic and axo-somatic synapses. These peptide-containing terminals do not seem to differ in any way from classic transmitter-containing synapses in the brain. The synaptic contacts between hypothalamo-rhombencephalic fibres on the one hand and neurons of the nucleus tractus solitarii and the dorsal motor nucleus of vagus on the other might be the morphological representation of an involvement of the paraventricular nucleus in cerebral cardiovascular regulation.
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PMID:[Immunocytochemical studies on the possible involvement of the classical neurosecretory system in the cerebral processes of cardiovascular regulation]. 391 Jul 22

Oxytocin-containing neurons and axon terminals contacting the neurons of the rat paraventricular nucleus were investigated by the peroxidase-antiperoxidase technique for light and electron microscopy. At the light microscopic level the reaction product was seen to fill the somata, dendrites and axons of the neurons. At the ultrastructural level the immunoprecipitate was localized on cytoplasm (including ergastoplasm) and neurosecretory granules (NSG) of the somata; microtubules, ergastoplasm and NSG of the dendrites; and NSG of the axons. Axon terminals synapsing on the surface of the labelled somata and dendrites were exclusively unlabelled. The somata and dendrites were observed to receive both asymmetrical (Gray's type I) and symmetrical (Gray's type II) synapses with clear, mostly spherical and flattened vesicles, respectively. Frequently, pleomorphic vesicles and a few densecore vesicles occurred in both types of synapses. There also were present some unlabelled bridge-like axon terminals making 'double' synapses either on two labelled dendritic processes or on one unlabelled and one labelled dendrite. The present findings demonstrate that the somata and dendrites of the oxytocin-containing neurons receive diverse innervation. At the same time there was no evidence in this study for synaptic input to the labelled axons of the neurons.
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PMID:A light and electron microscopic study of oxytocin-containing neurons in the paraventricular nucleus of the rat. 391 66

The presence of oxytocin, vasopressin and neurophysin in the testis of adult Wistar and Brattleboro rats has been examined immunocytochemically. After fixation in modified Bouin's solution, or Bouin's sublimate fixative, immunostaining was accomplished with the peroxidase-antiperoxidase method. The presence of immunoreactive oxytocin was demonstrated in 80% of the interstitial cell population of both rat strains while no staining was observed for vasopressin or neurophysin.
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PMID:Immunocytochemical evidence for the presence of oxytocin in rat testis. 399 64

The isolated urinary bladder of the toad responds to neurohypophyseal hormone with a net increase of water transport from the mucosal to the serosal solution in the presence of an osmotic gradient. This response is mediated intracellularly by cyclic 3',5'-adenosine monophosphate (AMP). The present study demonstrates that hydroosmotically active substances such as oxytocin, dibutyryl cyclic 3',5'-AMP, and theophylline, but not hydroosmotically inactive substances, induce the uptake of horseradish peroxidase from the mucosal solution. Peroxidase taken up by the mucosal cells is demonstrable in small tubules and vesicles, and eventually accumulates in lysosomes. The uptake of peroxidase from the serosal solution into similar bodies in the mucosal cells is not hormone-dependent. It is also shown that peroxidase does not penetrate the tight junction from either the mucosal or serosal solution. These results extend previous findings which implicated the apical membrane of the mucosal epithelium as the site affected by neurohypophyseal hormones. A mechanism based on secretory phenomena is proposed as a framework for future investigations of apical membrane permeability changes and pinocytosis.
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PMID:Correlation between pinocytosis and hydroosmosis induced by neurohypophyseal hormones and mediated by adenosine 3',5'-cyclic monophosphate. 432 55

The comparative distribution of nine peptides was examined in the L4 segment of the rat cord using the peroxidase antiperoxidase technique. The peptides examined were substance P, neurotensin, cholecystokinin, methionine-enkephalin, oxytocin, neurophysin, adrenocorticotrophin, thyrotropin releasing hormone, and vasoactive intestinal polypeptide. No transport blocking agents were used and in spite of this cell bodies containing substance P, neurotensin, cholecystokinin, and methionine-enkephalin were observed. All peptides except for thyrotropin releasing hormone were observed in fibers in laminae I and II. All peptides were present in the area around the central canal, lamina X. Each peptide had its own characteristic distribution within fibers in the gray and white matter.
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PMID:The distribution of nine peptides in rat spinal cord with special emphasis on the substantia gelatinosa and on the area around the central canal (lamina X). 616 70

Immunohistochemical and horseradish peroxidase (HRP) studies suggest that oxytocin-stained fibers from the paraventricular nucleus of the hypothalamus (PVH) innervate the locus coeruleus (LC) and dorsal vagal complex (DVC) in the brainstem of the rat, and that adrenergic fibers from the LC and DVC in turn project to the PVH. It is hypothesized that these pathways are directly involved in the integration of neuroendocrine and autonomic responses in the periphery, as well as in the mediation of homeostasis-preserving responses within the CNS itself.
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PMID:Biochemical specificity in central pathways related to peripheral and intracerebral homeostatic functions. 618 2

The axonal endoplasmic reticulum (ER) and synaptic-like (micro)vesicles within axon terminals of the neurohypophysis and their contribution to the secretory process in hypothalamo-neurohypophysial neurons have been investigated cytochemically in normal mice and in mice given 2% salt water to drink for stimulation of hormone synthesis in and release from these neurons. Cytochemical techniques included the peroxidase-antiperoxidase (PAP) immunocytochemical method for localization of neurophysin, wheat germ agglutinin-horseradish peroxidase (WGA-HRP) as a tracer for the anterograde axonal transport of membrane from within the perikaryon, and blood-borne native horseradish peroxidase (HRP) as a tracer for internalized axon terminal membrane. The primary antiserum employed was directed against neurophysins I and II, the carrier proteins for the peptide hormones oxytocin and vasopressin, respectively. PAP reaction product was observed over neurosecretory granules but never over the endoplasmic reticulum, microvesicles or other organelles in axons and terminals of the neurohypophysis. WGA-HRP was delivered extracellularly to cell bodies of paraventricular neurons by cerebral ventriculocisternal perfusion. Internalized perikaryal surface membrane tagged with WGA-HRP was recycled through the innermost Golgi saccule (GERL) from which neurosecretory granules were formed. The anterograde axonal transport of membrane-bound WGA-HRP was manifested within the neurosecretory granules; WGA-HRP did not label the axonal reticulum or terminal microvesicles in the neurohypophysis. Blood-borne native HRP endocytosed into neurohypophysial terminals was associated with a plethora of microvesicles measuring 40-70 nm in diameter and vacuoles similar in size to the 100-300-nm-wide neurosecretory granules. The microvesicles contributed to the formation of numerous vacuoles. The internalization of axon terminal membrane as microvesicles incorporating HRP was quantitatively greater than vacuoles in both salt-stressed and control mice. The results suggest that in the hypothalamo-neurohypophysial system of the mouse the axonal ER and terminal microvesicles are not involved in the transport, storage, and exocytosis of neurosecretory material and perhaps other molecules processed through the innermost Golgi saccule. Nevertheless, a prominent population of the microvesicles within axon terminals of the neurohypophysis does participate in the secretory process. These vesicles are involved directly in the internalization of the terminal surface membrane subsequent to release of secretory granule content.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Further studies of the secretory process in hypothalamo-neurohypophysial neurons: an analysis using immunocytochemistry, wheat germ agglutinin-peroxidase, and native peroxidase. 620 13


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