Regulation of cholecystokinin receptors in the ventromedial nucleus of the hypothalamus: sex steroid hormone effects.
Quantitative autoradiography was used to analyze cholecystokinin receptor (CCK-R) binding in the ventromedial hypothalamic nucleus (VMH) of gonadectomized rats treated with estrogen or testosterone. In the rostral VMH, sex steroids did not affect binding levels. In the caudal VMH, in both gonadectomized male and female rats, the levels of CCK-R binding were decreased 24 h after injection of 50 micrograms of estrogen benzoate but were not changed after injection of 300 micrograms of testosterone propionate. We hypothesize that these changes in CCK-R binding in the VMH reflect ligand-induced down-regulation that result from an estrogen-facilitation of stimulated CCK release in the VMH.
Popper
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P
Department of Neurobiology, UCLA School of Medicine 90025-1763, USA.
Priest
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CA
Micevych
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PE
D000818:Animals; D001345:Autoradiography; D015536:Down-Regulation / Q000187:drug effects; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D012739:Gonadal Steroid Hormones / Q000494:pharmacology*; D007457:Iodine Radioisotopes; D008297:Male; D009919:Orchiectomy; D010052:Ovariectomy; D051381:Rats; D011949:Receptors, Cholecystokinin / Q000187:drug effects / Q000378:metabolism*; D012727:Sex Characteristics; D013739:Testosterone / Q000494:pharmacology; D014697:Ventromedial Hypothalamic Nucleus / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*
D012739:Gonadal Steroid Hormones; D007457:Iodine Radioisotopes; D011949:Receptors, Cholecystokinin; D013739:Testosterone; D004958:Estradiol