Please use this identifier to cite or link to this item: http://ahro.austin.org.au/austinjspui/handle/1/9288
Title: Galanin-like peptide mRNA in neural lobe of rat pituitary. Increased expression after osmotic stimulation suggests a role for galanin-like peptide in neuron-glial interactions and/or neurosecretion.
Authors: Shen, J;Larm, J A;Gundlach, Andrew L
Affiliation: Department of Medicine, University of Melbourne, Austin & Repatriation Medical Centre, Heidelberg, Vic., Australia.
Issue Date: 1-Jan-2001
Citation: Neuroendocrinology; 73(1): 2-11
Abstract: Galanin-like peptide (GALP) was recently identified in the porcine hypothalamus, pituitary gland and gut, and has reported selectivity for the GalR2, c.f. the GalR1 receptor. GALP cDNAs have been cloned from pig, rat and human, and GALP mRNA expression is restricted to the arcuate nucleus in normal rat brain. This study examined the regional and cellular distribution of GALP mRNA in the rat pituitary gland, and subsequently determined the effect of osmotic stimulation on GALP transcript levels. GALP mRNA was not detected in the anterior or intermediate lobes, but moderate levels of GALP mRNA were present in the neural (posterior) lobe, in presumed pituicytes, of normal male and female rats. Osmotic stimulation by dehydration or salt loading produced a time-dependent increase in GALP mRNA levels in the neural lobe. Thus, dehydration for 4 days increased GALP mRNA 40-fold, while salt loading for 4, 7 or 10 days increased GALP levels 14-, 21- and 25-fold, respectively (p < or = 0.001). Levels of vasopressin (VP) mRNA in the neural lobe were also increased by these treatments, consistent with previous reports. Galanin (GAL) and GalR2 receptor mRNAs were not detected in the neural lobe, under normal or osmotic stimulation conditions. In addition, GALP mRNA levels in the arcuate nucleus were not altered in dehydrated or salt-loaded rats; and GALP mRNA was not detected in magnocellular neurons of the supraoptic or paraventricular nucleus, despite the characteristic up-regulation of VP and GAL mRNA in these cells. In view of the established anatomy and function of VP/oxytocin neurons in the hypothalamo-neurohypophysial system and the role played by pituicytes in their regulation, the likely synthesis/release of GALP by these specialized astrocytes strongly suggests a role for this novel peptide in regulation of pituicyte morphology/function and/or neurohormone release.
Internal ID Number: 11174012
URI: http://ahro.austin.org.au/austinjspui/handle/1/9288
DOI: 54615
URL: http://www.ncbi.nlm.nih.gov/pubmed/11174012
Type: Journal Article
Subjects: Animals
Female
Galanin-Like Peptide
Gene Expression.physiology
Hypothalamus.physiology
In Situ Hybridization
Male
Nerve Tissue Proteins.genetics
Pituitary Gland, Posterior.physiology
Presynaptic Terminals.metabolism
RNA, Messenger.analysis
Rats
Rats, Sprague-Dawley
Receptors, Galanin
Receptors, Neuropeptide.genetics
Vasopressins.genetics
Water-Electrolyte Balance.physiology
Appears in Collections:Journal articles

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