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

1. Frozen and paraffin sections of six species of trematodes: Schistosoma mansoni, S. mattheei, S. japonicum, Schistosomatium douthitti, Echinostoma paraensei and Fasciola hepatica have been incubated with antisera against leu-enkephalin, FMRF-amide, gastrin-17, luteinizing hormone releasing hormone, neurotensin, oxytocin, prolactin, substance P, thyroid stimulating hormone and cholecystokinin, using indirect immunofluorescence and biotin-avidin horseradish peroxidase detection systems. 2. Of the ten antisera tested, six (leu-enkephalin, FMRF-amide, gastrin-17, luteinizing hormone releasing hormone, substance P and cholecystokinin) showed significant immunoreactivity, primarily in the central and peripheral nervous system, and also perhaps in the osmoregulatory system of the three species of Schistosoma. 3. Immunopositive nerve fibers extended from ganglia to gut wall, uterus and vitelline follicles, and especially from subtegumental nerve plexi to sensory receptors on the surface or in dorsal nippled tubercles.
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PMID:Immunocytochemical localization of regulatory peptides in six species of trematode parasites. 290 70

Genomic DNA of Israeli Holstein-Friesian dairy cattle were screened with a battery of 17 cloned or subcloned DNA probes in an attempt to document restriction fragment length polymorphisms at a number of genetic loci. Restriction fragment length polymorphisms were observed at the chymosin, oxytocin-neurophysin I, lutropin beta, keratin III, keratin VI, keratin VII, prolactin, and dihydrofolate reductase loci. Use of certain genomic DNA fragments as probes produced hybridization patterns indicative of satellite DNA at the respective loci. Means for distinguishing hybridizations to coding sequences for unique genes from those to satellite DNA were developed. Results of this study are discussed in terms of strategy for the systematic development of large numbers of bovine genomic polymorphisms.
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PMID:Screening of Israeli Holstein-Friesian cattle for restriction fragment length polymorphisms using homologous and heterologous deoxyribonucleic acid probes. 290 50

Nipple stimulation by pregnant women close to term results in oxytocin release, as reflected by increased levels of oxytocin in peripheral plasma. This appears to be a specific response, and it does not involve either vasopressin or prolactin release.
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PMID:Oxytocin, vasopressin, and prolactin responses associated with nipple stimulation. 291 46

Effects of Dehydroepiandrosterone-Sulfate (DHA-S) administration during the induction of labor were analysed comprehensively in 116 cases of primipara without any complications. In all of the patients delivery was induced by means of intravenous drip infusion of oxytocin. DHA-S was given as follows; Group A: no administration of DHA-S, Group B: intravenous drip infusion of 600 mg of DHA-S, Group C: intravenous injection of 200 mg of DHA-S every two hours (max, five times). The duration of the first and second stages of labor was reduced significantly in Group C compared to that of Group A (p less than 0.02). Serum DHA-S and estradiol levels in the patients in Groups B and C were significantly higher than those in Group A during the induction of the labor (p less than 0.05-0.005). The secretion of maternal milk was suppressed transiently by the administration of DHA-S (p less than 0.05-0.005), and there was a significant negative correlation between the total amount of maternal milk secretion and the total dose of DHA-S (r = -0.6320, p less than 0.005). Maternal serum prolactin levels did not change significantly following the administration of DHA-S, but estradiol increased significantly following the administration of DHA-S until 48 hours after delivery. These facts suggested that the intravenous injection of 200mg of DHA-S every two hours was effective in assisting the induction of labor, and the transient suppression of maternal milk secretion due to the administration of DHA-S might be caused by the high level of maternal serum estradiol which was converted from DHA-S in the placenta.
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PMID:[Comprehensive approach to the clinical study of the administration of dehydroepiandrosterone-sulfate (DHA-S) during the induction of labor]. 294 85

We have developed and validated a push-pull technique that allows focal perfusion of the ovary in unanesthetized freely moving rats. We have used this method to investigate the intraovarian secretion of catecholamines (dopamine, norepinephrine, epinephrine), oxytocin, beta-endorphin and gamma-amino-butyric acid (GABA) during the estrous cycle. Cycling animals were implanted with ovarian push-pull catheters and jugular vein catheters under ether anaesthesia on proestrus, estrus and diestrous Day 2. This procedure did not disrupt normal preovulatory release of prolactin and luteinizing hormone (LH). Thus, perfusion of the ovary and simultaneous monitoring of hormone levels in systemic blood in freely moving rats allow correlation of the temporal relationship of ovarian events with cyclic gonadotropin secretion. The results clearly indicate that a rise in ovarian norepinephrine occurs concomitant with the preovulatory surge in prolactin and LH. Ovarian beta-endorphin concentrations exhibit cyclic changes, whereas GABA release rates remain stable throughout the cycle. Oxytocin is secreted by ovarian tissue, and the secretion rate appears to be inversely related to prolactin. In view of the proposed involvement of ovarian nerves and particularly catecholamines in the process of follicular maturation and ovulation, our findings suggest a preovulatory activation of ovarian noradrenergic sympathetic neurons.
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PMID:Intraovarian secretion of catecholamines, oxytocin, beta-endorphin, and gamma-amino-butyric-acid in freely moving rats: development of a push-pull tubing method. 294 38

This article reviews the current state of our knowledge about the hormonal basis of maternal behavior in the rat. Considered are the ovarian hormones estrogen and progesterone, the pituitary hormones beta-endorphin and prolactin, and the hormone oxytocin, secreted by several hypothalamic nuclei and associated brain regions. The hormones of pregnancy, estrogen and progesterone, prime the female to respond to a terminal rise in estrogen that stimulates a high level of maternal responsiveness even before parturition begins. Studies on the role of prolactin, using hypophysectomy, prolactin release blockers and anterior pituitary and prolactin replacement, indicate that prolactin is required for the ovarian hormones to be effective in stimulating maternal behavior. During the latter half of pregnancy, placental lactogen may displace prolactin in this role. Although prolactin serves as a chronic stimulus for maternal behavior, it also may act over a short period. Oxytocin stimulates maternal behavior in a specific strain of rat, but not in other strains, and only when administered introcerebroventricularly (ICV) in estrogen-primed females. The decline in the high brain levels of beta-endorphin around parturition has been proposed as a requirement for the onset of maternal behavior; morphine blocks the onset of maternal behavior and disrupts ongoing maternal behavior and maternal aggression in lactating females. However, blocking beta-endorphin action at parturition interferes with pup cleaning and eating of the placenta as well.
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PMID:Hormonal basis during pregnancy for the onset of maternal behavior in the rat. 296 17

We have recently shown that the posterior pituitary (neurointermediate lobe) contains a potent prolactin (PRL)-releasing factor (PRF) which is distinct from known PRL secretagogues. Posterior pituitary PRF appears to be a small peptide of an unknown cellular origin. Using pituitary stalk-sectioned (SS) male rats, the objectives of this study were: (1) to determine if PRF is transported from the hypothalamus or is synthesized within the pituitary gland, and (2) to compare changes in PRF activity with alterations in the posterior pituitary content of beta-endorphin (beta-END), oxytocin (OXY), and dopamine (DA). One or two weeks following pituitary SS or sham surgery (SHAM), acid extracts of the posterior pituitary and medial basal hypothalamus (MBH) were analyzed for their hormone content. PRF activity was assessed by determining the stimulation of PRL secretion from perifused anterior pituitary cells, DA was measured by HPLC, and OXY and beta-END levels were determined by RIAs. OXY and DA concentrations in the posterior pituitary were reduced more than 95% at both 1 and 2 weeks after SS. PRF activity in the posterior pituitary was significantly reduced by 75 and 90%, 1 and 2 weeks after SS, respectively. In contrast, beta-END levels in the posterior pituitary at these times increased 20 and 60%, as compared to SHAM rats. Unlike the posterior pituitary, OXY levels in the MBH increased 123% 1 week following SS, and 1,260% at 2 weeks. These increases may reflect the accumulation of OXY-containing secretory vesicles in the severed nerves. DA concentrations in the MBH showed a biphasic pattern. DA levels were initially decreased by 70%, and then increased, but remained 30% below SHAM levels. The reason for these alterations in DA levels is not clear.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differential effects of pituitary stalk-section on posterior pituitary and hypothalamic contents of prolactin-releasing factor, oxytocin, dopamine and beta-endorphin. 297 37

This consideration of the influence of endogenous opioid peptide systems on GnRH and oxytocin neurones serves to illustrate some of their possible regulatory interactions with other neuroendocrine systems. Opioids are known to influence the secretion of all the anterior pituitary hormones (see Grossman & Rees, 1983) and these effects are likely to be mediated, at least in part, in the hypothalamus. For example, inhibitory effects of opioids have also been described on secretion from the median eminence of somatostatin (Drouva et al. 1981b) and dopamine (Wilkes & Yen, 1980), and this site of action probably accounts for at least some of the stimulatory effects of exogenous opioids on plasma growth hormone and prolactin levels respectively. For the GnRH neurones the influence of endogenous opioid neurones, possibly the arcuate beta-endorphin system, appears to be mediated indirectly by inhibiting release of excitatory or facilitatory monoamines. This opioid-adrenergic interaction itself appears to be central in the regulation of gonadotrophin secretion and mediation of the feedback effects of gonadal steroids in the brain. The steroids may act directly on both adrenergic and opioid neurones, altering monoamine metabolism and release which may, in turn, regulate numbers of adrenergic receptors perhaps located on the GnRH neurones. Opioid peptide levels are also modulated by steroids probably reflecting altered synthesis and/or processing of precursors. Regulation of the opioid-adrenergic input may not only acutely affect the secretory output of the GnRH neurones but also influence synthesis or processing of GnRH itself (see Kalra & Kalra, 1984) and its degradation by hypothalamic peptidases (Advis, Krause & McKelvy, 1983). Oxytocin neurones demonstrate three further levels of interaction with endogenous opioid peptides. First the anatomical organization of the oxytocin neurones has enabled a clear demonstration of the action of opioids close to the secretory terminals to uncouple the generation of electrical activity from release of peptide. Secondly, both the oxytocin and the neighbouring vasopressin neurones themselves synthesize, process and package opioid peptides. These neurones thus provide a clear example of co-existence of several biologically active products in individual neurones. The relative expression of the different gene products may prove to be a further level of control of opioid influences on the oxytocin and vasopressin neurones.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Endogenous opioid peptides and hypothalamic neuroendocrine neurones. 299 85

Extracellular action potentials were recorded from 48 single units located in the hypothalamic arcuate and ventromedial nuclei. Fifteen percent of the cells were identified as projecting to the median eminence and some of these cells may have belonged to the tuberoinfundibular dopaminergic systems. Responses of all cells to stimulation of the ipsilateral supraoptic nucleus were recorded; 17% of ventromedial nucleus neurons were antidromically identified as projecting to the supraoptic nucleus. None of the latter cells was also identified as projecting to the median eminence. Three of six identified tuberoinfundibular and eight unidentified ventromedial nucleus cells were found to be excited by stimulation of the supraoptic nucleus. One arcuate cell identified as projecting to the median eminence was nonresponsive to supraoptic stimulation. Orthodromic inhibitory responses were recorded from 17% of all cells recorded but no inhibitory responses were recorded from cells identified as projecting to the median eminence. We suggest that these results may provide some neurophysiologic explanations for the observed interrelationships between oxytocin and prolactin secretion, and between vasopressin and growth hormone secretion.
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PMID:Electrophysiologic evidence for connections between the supraoptic and the arcuate/ventromedial hypothalamic nuclei in the rat. 301 86

Subcutaneous administration of arginine vasopressin (AVP) to conscious rats induced a dose-dependent increase of plasma ACTH and beta-endorphin levels and decrease of plasma prolactin (PRL) levels 30 min later. AVP similarly reduced PRL increase induced by exposure to a novel environment stress. Oxytocin (OT) was also active but 5-fold less potent than AVP. The study of several analogs with specific agonistic and antagonistic activity on the oxytocic, vasopressor and antidiuretic receptors of OT and AVP suggests that the receptor involved in this effect does not fit into this classification.
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PMID:Vasopressin and oxytocin reduce plasma prolactin levels of conscious rats in basal and stress conditions. Study of the characteristics of the receptor involved. 302 94


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