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)

The effects of local postlearning microinjections of arginine-vasopressin (AVP) and oxytocin (OXT) on one-trial learning passive avoidance behavior and the influence of AVP on alpha-MPT-induced disappearance of norepinephrine (NE) and dopamine (DA) in discrete brain regions have been studied in the rat. OXT injected bilaterally in the hippocampal dentate gyrus (25-25 pg) or in the midbrain dorsal raphe nucleus (50 pg) significantly attenuated passive avoidance behavior. Facilitation of passive avoidance behavior was observed when the peptide was injected into the dorsal septal nucleus. AVP facilitated passive avoidance behavior when administered into the hippocampal dentate gyrus, dorsal raphe nucleus or dorsal septal nucleus. Injection of either neuropeptides into the central amygdaloid nucleus appeared to be ineffective. One week after the behavioral experiments a repeated injection of AVP into the hippocampal dentate gyrus increased the disappearance of NE in the dentate gyrus and in the nucleus ruber. An injection into the dorsal septal nuclei decreased the NE disappearance in the dorsal septal nucleus itself and increased it in the nucleus ruber. Injection in the dorsal raphe nucleus led to an increase in the disappearance of DA in the locus coeruleus and in the nucleus ruber. It is concluded that memory consolidation can be oppositely influenced by local application of minute amounts of either OXT or AVP into certain limbic-midbrain structures, suggesting an involvement of these brain regions in the memory effects of these peptides. Modulation of catecholamine turnover in specific brain areas after AVP administration may be related to this behavioral effect.
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PMID:Effect of oxytocin and vasopressin on memory consolidation: sites of action and catecholaminergic correlates after local microinjection into limbic-midbrain structures. 48 59

Oxytocin (OXT) attenuates memory processes and endogenous OXT might be regarded as an amnesic neuropeptide. In this study, the mode of action of OXT on brain catecholaminergic neurotransmission has been analyzed. Peripheral injection of OXT facilitated the alpha-MPT-induced disappearance of noradrenaline (NA) in the mesencephalon. Dopamine (DA) disappearance was inhibited in the mesencephalon and facilitated in the striatum. The accelerated striatal DA disappearance was not observed if the peptide was given together with alpha-MPT, but only if OXT was injected after alpha-MPT treatment. Intraventricular injection of OXT or des-glycinamide-oxytocin (DG-OXT) caused a decrease in the DA disappearance in the mesencephalon, whereas central administration of anti-oxytocin serum (anti-OXT) accelerated the DA disappearance in the same region. The data raise the possibility that DA utilization in the mesencephalon may be correlated with the influence of OXT on CNS processes.
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PMID:Effects of oxytocin, des-glycinamide-oxytocin and anti-oxytocin serum on the alpha-MPT-induced disappearance of catecholamines in the rat brain. 613 95

The effects of Pro-Leu-GlyNH2 (PLG), administered i.c.v. in doses of 3.5, 35, 350 and 3500 pmol, were studied on the alpha-MPT-induced disappearance of catecholamines in microdissected rat brain nuclei. PLG, dose-dependently, increased dopamine disappearance in the nucleus caudatus and globus pallidus, whereas a decrease in dopamine disappearance was observed in the nucleus dorsomedialis. Noradrenaline disappearance was decreased in the medial septal nucleus, anterior hypothalamic area and lateral amygdala. A tendency towards an increase in noradrenaline disappearance was observed in the nucl. supraopticus. These data show that PLG has a central site of action. The effects of PLG on dopamine disappearance are comparable to those previously found with vasopressin, while the effects of PLG on noradrenaline utilization show a striking similarity with those previously obtained with oxytocin.
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PMID:Pro-Leu-GlyNH2 affects dopamine and noradrenaline utilization in rat limbic-forebrain nuclei. 615 Jul 49

The release of oxytocin from isolated posterior lobe of the hypophysis of untreated rats and rats pretreated with alpha-methyl-p-tyrosine (alpha-MPT) has been studied. The amount of oxytocin released under resting conditions, in response to ouabain was much higher in those preparations which had been pretreated with alpha-MPT. Dopamine failed to affect the resting release in tissue taken from control rats but it significantly reduced the secretion of oxytocin in tissue dissected from dopamine-deficient rats. Opioid peptides, beta-endorphin or D-Ala2-Pro5-enkephalinamide enhanced the release of oxytocin from isolated neural lobe of the hypophysis dissected from untreated rats, but they failed to enhance significantly the release from posterior lobe of rats which had been pretreated by alpha-MPT. Naloxone prevented the effect of the opioid peptides, and by itself significantly reduced the release of oxytocin. The data suggest that (i) dopamine stored in, and released from, the neural lobe may inhibit the secretion of oxytocin; (ii) the release of oxytocin may be continously controlled by an endogenous opioid peptide: opioid peptides may exert their effect via a disinhibitory phenomenon; they remove the inhibitory effect of dopamine on oxytocin release possibly by inhibiting the release of dopamine.
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PMID:Inhibition of dopamine of oxytocin release from isolated posterior lobe of the hypophysis of the rat; disinhibitory effect of beta-endorphin/enkephalin. 739 4

Noradrenaline and serotonin are known to control arginine-vasopressin (AVP) and oxytocin (OT) secretion in the systemic circulation. The aim of the current study was to investigate whether these monoamines are also able to influence AVP and OT expression in the paraventricular (PVN) and supraoptic nuclei (SON). To test this hypothesis, we used the Tg8 transgenic mice KO for the monoamine oxidase-A gene, which present high levels of noradrenaline and serotonin in the brain. AVP and OT expression were evaluated at peptide and mRNA levels by immunohistochemistry, enzyme immunoassay, and in situ hybridization. Compared with wild type, the amounts of AVP, OT, AVP mRNA, and OT mRNA were increased in the PVN and SON in Tg8 mice. To distinguish the respective contributions of noradrenaline and serotonin to these modifications, we treated Tg8 mice with a synthesis inhibitor of either catecholamines [alpha-methylparatyrosine (alpha-MPT)] or serotonin [parachlorophenylalanine (pCPA)]. Administration of alpha-MPT to Tg8 mice induced a decline in the amounts of AVP, OT, and their mRNA in the PVN and SON. The pCPA treatment in Tg8 mice was also associated with a decrease in OT expression in the PVN and SON and in AVP expression in the PVN, but not in the SON. These results suggest that noradrenaline may activate AVP and OT expression in the PVN and SON. Likewise, serotonin is proposed to stimulate AVP and OT expression in the PVN and only OT expression in the SON.
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PMID:Activation by serotonin and noradrenaline of vasopressin and oxytocin expression in the mouse paraventricular and supraoptic nuclei. 1188 Apr 81