| Oxytocin release in magnocellular nuclei: neurochemical mediators and functional significance during gestation. | |
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MedLine Citation:
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PMID: 20554931 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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When released from dendrites within the supraoptic (SON) and paraventricular (PVN) nuclei (intranuclear release) during suckling, oxytocin exerts autocrine and paracrine effects on oxytocin neurons that are necessary for the unique timing and episodic pattern of oxytocin release into the systemic circulation that is characteristic of lactation. Recent reports have shown that stimulation of central noradrenergic and histaminergic receptors are both necessary for intranuclear release of oxytocin in response to suckling. In addition, in vitro studies indicate that excitatory amino acids may also be critical for central oxytocin secretion, although in vivo experiments have not provided direct support for this hypothesis. In addition to a critical role in intranuclear oxytocin release during lactation, norepinephrine has also been shown to stimulate central oxytocin during gestation. Stimulation of central oxytocin receptors during gestation appears critical for normal systemic oxytocin secretion in responses to suckling during the subsequent period of lactation. Oxytocin receptor blockade during pregnancy alters normal timing of systemic oxytocin release during suckling and reduces milk delivery. Several adaptations occur in the central oxytocin system that are necessary for determining the unique response characteristic observed during parturition and gestation. Central oxytocin receptor stimulation during gestation has been implicated in pregnancy-related morphological changes in magnocellular oxytocin neurons, disinhibition of oxytocin neurons to GABA, and adaptations in membrane response characteristics of oxytocin neurons. In conclusion, intranuclear oxytocin release during gestation and lactation are critical for establishing, and then evoking the unique pattern of systemic oxytocin secretion in response to the suckling offspring necessary for adequate milk delivery. Furthermore, activation of central noradrenergic receptors appears to be critical for release of central oxytocin in both of these reproductive states. |
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Authors:
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Steven L Bealer; William E Armstrong; William R Crowley |
Publication Detail:
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Type: Journal Article; Research Support, N.I.H., Extramural; Review Date: 2010-06-16 |
Journal Detail:
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Title: American journal of physiology. Regulatory, integrative and comparative physiology Volume: 299 ISSN: 1522-1490 ISO Abbreviation: Am. J. Physiol. Regul. Integr. Comp. Physiol. Publication Date: 2010 Aug |
Date Detail:
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Created Date: 2010-08-03 Completed Date: 2010-09-08 Revised Date: - |
Medline Journal Info:
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Nlm Unique ID: 100901230 Medline TA: Am J Physiol Regul Integr Comp Physiol Country: United States |
Other Details:
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Languages: eng Pagination: R452-8 Citation Subset: IM |
Affiliation:
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Dept. of Pharmacology and Toxicology, Univ. of Utah, 30 South 2000 East, Rm 201, Salt Lake City, UT 84112, USA. steven.bealer@utah.edu |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Action Potentials Animals Animals, Suckling Breast Feeding Excitatory Amino Acids / metabolism Female Gene Expression Regulation, Developmental Gestational Age Histamine / metabolism Humans Lactation Neurons / metabolism, secretion* Neurotransmitter Agents / metabolism* Norepinephrine / metabolism Opioid Peptides / metabolism Oxytocin / genetics, metabolism, secretion* Paraventricular Hypothalamic Nucleus / embryology, metabolism, secretion* Pregnancy Signal Transduction* |
| Grant Support | |
ID/Acronym/Agency:
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HD-13703/HD/NICHD NIH HHS; HD-38243/HD/NICHD NIH HHS; NS-23941/NS/NINDS NIH HHS |
| Chemical | |
Reg. No./Substance:
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0/Excitatory Amino Acids; 0/Neurotransmitter Agents; 0/Opioid Peptides; 50-56-6/Oxytocin; 51-41-2/Norepinephrine; 51-45-6/Histamine |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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