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)

Light microscopic observations using Nomarski optics on the aldehyde-fixed hypothalamus of normal adult cats, monkeys and rabbits revealed the presence of cells in the supraoptic, paraventricular and periventricular nuclei which possessed yellow birefringent inclusions. Immunogold labelling showed that in each species the cells displayed oxytocin-like immunoreactivity, both in electron-dense inclusions within some (but not all) cisterns of rough endoplasmic reticulum and in secretory granules. The cells in cats and rabbits were in all respects indistinguishable from the homologous 'birefringent' cells previously described in rats, but in monkeys, cells frequently contained additional inclusions in cisterns of rough endoplasmic reticulum which did not display oxytocin or vasopressin-like immunoreactivity, even after trypsin, pepsin or chymotrypsin treatment of sections. Observations on cats and rabbits using fluorescence microscopy revealed that the birefringent cells possessed bright autofluorescence which facilitated the identification of more cells than were seen using Nomarski optics alone. Autofluorescence was abolished when sections were mounted in glycerol, or when exposed to light for protracted periods of time. Attempts to label for monoamines in these cells were not successful, suggesting that the fluorescence is not due to aldehyde-induced amine fluorescence. It is not clear why neuropeptides are retained in some rough endoplasmic reticulum cisterns. It is possible that these birefringent cells contain a peptide, or peptides, which are abnormal in some manner, or which may be other members of the oxytocin gene family. Alternatively, the processing of neuropeptides to permit their export to the Golgi apparatus may be deficient. Acetylcholinesterase (AChE) histochemistry revealed that, unlike other oxytocin neurons, cells with intracellular accretions lacked detectable acetyl cholinesterase. As AChE is a known peptidase, it may be involved in regulating peptide export from the rough endoplasmic reticulum.
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PMID:Neuropeptide accretions in the endoplasmic reticulum of oxytocinergic neurons in cats, monkeys and rabbits: a widespread phenomenon. 129 66

Effect of vasopressin, oxytocin and LHRH (10 and 20 pg/ml medium) on the proliferation and metabolism of cultured rat bone marrow stromal cells was investigated by methyl-3H-thymidine incorporation, cytochemistry and estimation of enzyme activities. Vasopressin did not change of the activity of tetrahydrofolate dehydrogenase (4HFDH), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PD) and the level of reduced glutathione (GSH). However, the higher concentration of vasopressin significantly lowered the activity of acetylcholinesterase (AchE). As compared with the control cultures, stromal cells grown in the presence of oxytocin showed higher (at lower hormone concentration) and lower (at higher concentration) LDH activity as well as lower G6PD activity (only at higher concentration), while the activity of AchE and the level of GSH was not changed. LHRH significantly increased G6PD and AchE activity and decreased LDH activity in the cultured cells. As revealed by cytochemistry, LHRH specifically enhanced 4HFDH activity in reticular cells.
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PMID:Effect of vasopressin, oxytocin and LHRH on the proliferation and metabolism of rat bone marrow stromal cells in culture. 176 8

It was found that acetylcholine (ACh) at the concentration of 10(-3) M inhibited ADH-stimulated water transport through the wall of amphibian urinary bladder. This effect was suggested to be caused by an interaction of ACh with acetylcholinesterase (AChE) rather than by a stimulation of the M- or N-cholinoreceptor. The inhibitory action of ACh was completely suppressed in the presence of various AChE inhibitors (physostigmine, proserine, armine, Gd-42, acridine-iodmethylate), while an inhibitor of butyrylcholinesterase (BuChE), AD-4, failed to affect it. In accord with this observation the activity of AChE (but not of BuChE) was demonstrated in the urinary bladder epithelium. Since, in addition to the hydrosmotic effects of pituitrine, 8-arginine-vasopressin or oxytocin, ACh blocked also effects of forskolin or cyclic AMP, one may conclude that it acts at some post-cyclic AMP production stage. AChE-dependent inhibition of the ADH-stimulated water transport decreased significantly when the serosal pH was raising from 7.2 to 8.0, but was augmented by serosal acidification (pH 6.8), whereas such pH alterations did not affect the activity of the epithelium AChE. The effect of ACh under consideration was suppressed by adding amiloride (10(-4) M) to the serosal solution. Similarly, the ACh effect was blocked by an inhibitor of Ca-dependent K+ channels, 4-aminopyrdine, which in addition prevented the inhibition of the ADH-stimulated water transport by the serosal acidification. It was noteworthy that some other K+ channel blockers (Ba2+, Cs+, tetraethylammonium, apamine, quinine) did not affect either the water transport or the antipituitrine effect of ACh. In conclusion, we suggest that the inhibitory action of ACh on the ADH-stimulated water transport in the urinary bladder is mediated through the intracellular acidification resulting from ACh interaction with AChE. It is unlikely that the acidification is merely a consequence of the ACh hydrolysis, rather the ACh-AChE interaction induces directly an increase in the proton conductivity of the basolateral membrane of the urinary bladder epithelium.
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PMID:[Acetylcholinesterase and the ADH-dependent transport of water in the amphibian bladder]. 181 71

Two nuclei, termed here the medial hypothalamic nucleus and the lateral hypothalamic retinorecipient nucleus, are possible homologs of the mammalian suprachiasmatic nucleus. As the mammalian suprachiasmatic nucleus is characterized by a dense concentration of vasoactive intestinal peptide (VIP)- and neurophysin (NP)-immunoreactive neurons and an absence of acetylcholinesterase (AChE) staining, we decided to examine these factors in the ring dove hypothalamus. Neither the medial hypothalamic nucleus nor the lateral hypothalamic retinorecipient nucleus contained either VIP- or NP-like immunoreactive neurons. The lateral hypothalamic retinorecipient nucleus stained darkly for AChE. Although there was some overlap in the distribution of VIP- and NP-like immunoreactive neurons, a clustering of both types into a well defined nucleus was not observed. Therefore, an avian homolog to the mammalian suprachiasmatic nucleus must differ in its chemoarchitecture from that of mammalian species described to date.
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PMID:Distribution of vasoactive intestinal peptide-like and neurophysin-like immunoreactive neurons and acetylcholinesterase staining in the ring dove hypothalamus with emphasis on the question of an avian suprachiasmatic nucleus. 233 26

Acetylcholinesterase activity was demonstrated histochemically at light- and electron-microscopic levels, in Vibratome sections of the supraoptic nucleus of fixed hypothalami derived from osmotically stimulated and unstimulated Long Evans rats, from homozygous Brattleboro rats with hypothalamic diabetes insipidus, from lactating rats, from normal adult male house mice (Mus musculus) and from mice with hereditary nephrogenic diabetes insipidus (di/di). Reaction product was located in supraoptic magnocellular neurons; in dorsal and rostral aspects of the supraoptic nuclei lightly stained cells predominate, whereas in ventral and caudal regions densely staining perikarya predominate. Pre- and post-embedding immunocytochemical detection of oxytocin-neurophysin or vasopressin-neurophysin, combined with acetylcholinesterase histochemistry, showed that the lightly staining cells are oxytocinergic, and the densely staining cells vasopressinergic. Osmotic stimulation of the animals, either by substitution of drinking water for 3 days with 2.5% saline or reason of genetic defects which result in diabetes insipidus, enhanced the acetylcholinesterase activity of the vasopressin neurons but had little effect on the weekly acetylcholinesterase-reactive oxytocin cells. Acetylcholinesterase activity was particularly marked in the hypertrophied abnormal magnocellular neurons of homozygous Brattleboro rats which do not release significant amounts of vasopressin. The increased acetylcholinesterase activity in osmotically stimulated animals cannot, therefore, be a function of vasopressin. Acetylcholinesterase activity was also detected in large multipolar neurons lying dorsolateral to the supraoptic nucleus, and in their fine axonal processes which project towards the supraoptic nucleus. A very few synaptic boutons surrounded by acetylcholinesterase reaction product were found in contact with magnocellular neuron basal dendrites. However, much of the punctate acetylcholinesterase reactivity observed at the light microscopic level and previously interpreted as representing the loci of cholinergic synaptic boutons was shown to be intracellular, and probably caused by acetylcholinesterase activity in some large, secondary lysosomes.
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PMID:Differential distribution of acetylcholinesterase activity among vasopressin- and oxytocin-containing supraoptic magnocellular neurons. 276 86

The release of vasoactive intestinal peptide (VIP) from the canine gut and its possible neural origin were studied using two agents, oxytocin and neostigmine, known to increase peripheral levels of VIP. Oxytocin and neostigmine increased the portal concentrations of VIP by threefold and sevenfold, respectively. A considerable portal/femoral vein gradient ranging from twofold in the basal state to sevenfold during stimulation with neostigmine indicated that the gut was the main source of circulating VIP. The contribution of the brain was minor, and that of the uterus was undetectable. Release of VIP occurred from the entire gut: After enterectomy, the residual gut (stomach, pancreas, and proximal duodenum) released spontaneously a large amount of VIP which masked the effect of oxytocin. Tetrodotoxin and hexamethonium, but not atropine, inhibited oxytocin-stimulted release of VIP by 80% and 60% respectively. This prompted the conclusion that the release of VIP was predominantly neurally mediated and that the chain of transmission involved a preganglionic cholinergic pathway. Hexamethonium strongly inhibited neostigmine-stimulated release of VIP. Atropine was even more potent in that it abolished the effect of neostigmine. The effect of atropine was attributed to a blockade of ganglionic muscarinic receptors, which are preferentially activated by cholinesterase inhibitors like neostigmine. The results of this study and those derived from electrical stimulation of the vagus nerve are consistent with the hypothesis that circulating VIP is released from intrinsic neurons of the gut under preganglionic cholinergic control.
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PMID:Neural release of vasoactive intestinal peptide from the gut. 743 34

The retinal innervation, cytoarchitectural, and immunohistochemical organization of the suprachiasmatic nucleus (SCN) was studied in the domestic sheep. The SCN is a large elongated nucleus extending rostrocaudally for roughly 3 mm in the hypothalamus. The morphology is unusual in that the rostral part of the nucleus extends out of the main mass of the hypothalamus onto the dorsal aspect of the optic chiasm. Following intraocular injection of wheat-germ agglutinin-horseradish peroxidase or tritiated amino acids, anterograde label is distributed throughout the SCN. Retinal innervation of the SCN is bilaterally symmetric or predominantly ipsilateral. Quantitative image analysis demonstrates that, although the amount of autoradiographic label is greatest in the ventral and central parts of the nucleus, density varies progressively between different regions. In addition to the SCN, retinal fibers are also seen in the medial preoptic area, the anterior and lateral hypothalamic area, the dorsomedial hypothalamus, the retrochiasmatic area, and the basal telencephalon. Whereas the SCN can be identified using several techniques, complete delineation of the nucleus requires combined tract tracing, cytoarchitectural, and histochemical criteria. Compared with the surrounding hypothalamic regions, the SCN contains smaller, more densely packed neurons, and is largely devoid of myelinated fibers. Cell soma sizes are smaller in the ventral SCN than in the dorsal or lateral parts, but an obvious regional transition is lacking. Using Nissl, myelin, acetylcholinesterase, and cytochrome oxidase staining, the SCN can be clearly distinguished in the rostral and medial regions, but is less differentiated toward the caudal pole. Immunohistochemical demonstration of several neuropeptides shows that the neurochemical organization of the sheep SCN is heterogeneous, but that it lacks a distinct compartmental organization. Populations of different neuropeptide-containing cells are found throughout the nucleus, although perikarya positive for vasoactive intestinal polypeptide and fibers labeled for methionine-enkephalin are predominant ventrally; neurophysin-immunoreactive cells are more prominent in the dorsal region and toward the caudal pole. The results suggest that the intrinsic organization of the sheep SCN is characterized by gradual regional transitions between different zones.
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PMID:The suprachiasmatic nucleus in the sheep: retinal projections and cytoarchitectural organization. 795 5

Induction of c-Fos expression in the supraoptic nucleus (SON) of the rat hypothalamus by endogenous acetylcholine was examined by microinfusion of neostigmine, a cholinesterase inhibitor, into the nucleus to locally accumulate the spontaneously released acetylcholine from the cholinergic terminals in the SON. Double staining of the neurosecretory neurons with antiserum to Fos, the protein product of c-Fos, and antiserum to vasopressin or oxytocin was performed. Fos-like immunoreactivity was manifested in both the vasopressin neurons and oxytocin neurons following the microinfusion of neostigmine. Microinfusion of nicotinic agonist, nicotine, to the SON also induced Fos expression, but mainly in the vasopressin neurons. Microinfusion of muscarinic agonist, carbachol, induced Fos expression as well, but mostly in the oxytocin neurons.
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PMID:Endogenous acetylcholine-induced Fos expression in magnocellular neurosecretory neurons in the supraoptic nucleus of the rat hypothalamus. 858 7

Long-term (2-12 weeks) cultures of adult guinea-pig ventricular myocytes, cocultured with neurons derived from stellate or intrinsic cardiac ganglia, retain their functional properties (Horackova et al., 1993, 1994, 1995). The present study was designed to investigate the morphological and immunochemical properties of such neurons and their associated cardiomyocytes. Cultured myocytes studied by means of phalloidin-rhodamine (for F-actin) and an antibody raised against myomes revealed parallel myofibrils with striations typical of rod-shaped cardiomyocytes, even while myocytes changed from cylindrical to flattened form as they established intercellular contacts. Microtubular networks, identified by alpha-tubulin DM1A antibody, were arrayed longitudinally in myofibrils, being especially prominent during the formation of intercellular contacts between myocytes. Histochemically identified adult peripheral autonomic neurons cultured alone or with myocytes displayed a variety of shapes. alpha-Tubulin staining was associated with the somata and neurites of various-shaped neurons whether cultured alone or with myocytes. Cultured neurons derived from stellate and intrinsic cardiac ganglia also exhibited staining for the general neuronal marker PGP 9.5 (protein gene product 9.5), and for specific markers of the following neurochemicals: tyrosine hydroxylase, acetylcholinesterase, choline acetyltransferase, neuropeptide Y, vasoactive intestinal peptide, calcitonin gene-related peptide, bradykinin, oxytocin, and NADPH-diaphorase. These data indicate that: (a) adult ventricular myocytes cocultured with intrathoracic neurons retain the structural properties of adult myocytes found in vivo; (b) intrinsic cardiac and extrinsic intrathoracic neurons cultured alone or with cardiomyocytes display morphological characteristics similar to those of neurons studied in situ; (c) intrinsic cardiac and intrathoracic extracardiac neurons cultured alone or with cardiomyocytes display a variety of morphologies (unipolar, bipolar, and multipolar), larger and more multipolar neurons being present in cultures derived from stellate versus intrinsic cardiac ganglia; (d) such cultured neurons are associated with a number of neurochemicals, more than one chemical being associated with each neuron. This model presents an excellent opportunity to study the morphology of individual peripheral extracardiac and intracardiac neurons as well as their potential to produce various neurochemicals that are known to be involved in the neuromodulation of cardiomyocyte function.
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PMID:Morphological and immunohistochemical properties of primary long-term cultures of adult guinea-pig ventricular cardiomyocytes with peripheral cardiac neurons. 876 Aug 56

Radioligand receptor autoradiography has shown that oxytocin- and vasopressin-binding sites exist in numerous rat brain regions, among which the amygdala and the bed nucleus of the stria terminalis (BST) are especially prominent. However, these descriptions did not take into account the numerous subdivisions of the amygdala and the BST. Thus, we have reinvestigated the distribution of these sites in the rat extended amygdala, which is formed by a continuum of structures stretching from the BST to the centromedial amygdala, including parts of the accumbens nucleus, substantia innominata, and transition areas between the amygdala and the striatum. For this purpose, histoautoradiography was used to detect binding sites at the cellular level, and anatomical boundaries were defined on the basis of acetylcholinesterase histochemistry and tyrosine-hydroxylase immunohistochemistry. Oxytocin- and vasopressin-binding sites were detected in well-defined subdivisions of both medial and central parts of the extended amygdala, but they almost never coexisted in the same region. Compared with previously reported distributions, our reinvestigation describes novel oxytocin- and vasopressin-binding sites in the lateral and supracapsular BST, in the sublenticular extended amygdala, in the interstitial nucleus of the posterior limb of the anterior commissure, in the marginal zone, in the central amygdaloid nucleus, and in the anterior amygdaloid area. These results indicate that oxytocin- and vasopressin-binding sites represent an important feature of the extended amygdala and may participate in the large variety of functions that characterize this area, including reproductive and ingestive behaviors, conditioned fear and autonomic regulation.
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PMID:Distribution of oxytocin- and vasopressin-binding sites in the rat extended amygdala: a histoautoradiographic study. 920 43


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