Are POMC neurons targets for sex steroids in the arcuate nucleus of the rat?
Testosterone alters the expression of proopiomelanocortin (POMC) mRNA in the neurons of the arcuate nucleus. While observations suggest that both estrogen and androgen receptors (AR) can mediate this action, only a negligible number of POMC neurons has previously been shown to contain estrogen receptor (ER)-alpha. To determine whether the putative action of testosterone is mediated via ER-beta or AR we double immuno- labeled hypothalamic sections from colchicine-pretreated male rats. Only few cells were immunostained for ER-beta and they were never found to co-localize POMC. In spite of the overlap in the anatomical distribution, only 3% of POMC cells appeared to contain AR. These results suggest that sex steroids have an indirect effect on most POMC neurons.
Fodor
M
M
Research Institute for Endocrinology, Reproduction and Metabolism, Vrije Universiteit University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
Delemarre-van de Waal
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HA
D000818:Animals; D000906:Antibodies; D001111:Arcuate Nucleus of Hypothalamus / Q000166:cytology / Q000502:physiology*; D003078:Colchicine; D004958:Estradiol / Q000502:physiology; D047628:Estrogen Receptor alpha; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000737:chemistry* / Q000502:physiology; D011333:Pro-Opiomelanocortin / Q000032:analysis* / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D011944:Receptors, Androgen / Q000032:analysis* / Q000276:immunology; D011960:Receptors, Estrogen / Q000032:analysis* / Q000276:immunology; D013739:Testosterone / Q000502:physiology; D001615:beta-Endorphin / Q000276:immunology
D000906:Antibodies; D047628:Estrogen Receptor alpha; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; D013739:Testosterone; D004958:Estradiol; D001615:beta-Endorphin; D011333:Pro-Opiomelanocortin; D003078:Colchicine