Kappa opioid receptor-mediated regulation of prolactin and alpha-melanocyte-stimulating hormone secretion in male and female rats.
The purpose of this study was to examine the effects of the kappa opioid receptor agonist U-50,488 and antagonist nor-binaltorphimine (NOR-BNI) on the secretion of prolactin and alpha-melanocyte-stimulating hormone (alpha MSH) in male and female rats. Activation of kappa opioid receptors with U-50,488 increased plasma prolactin concentrations in both male and female rats, whereas blockade of kappa opioid receptors with NOR-BNI decreased plasma prolactin concentrations in male, but not in female rats. U-50,488 also increased and NOR-BNI decreased plasma concentrations of alpha MSH; similar effects were observed in both male and female rats. These results reveal a sexual difference in kappa opioid receptor-mediated regulation of prolactin, but not alpha MSH secretion.
Department of Pharmacology and Toxicology, Michigan State University, East Lansing 48824.
J
J
Manzanares
E J
EJ
Wagner
K E
KE
Moore
K J
KJ
Lookingland
D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; D000818:Animals; D005260:Female; D008297:Male; D009271:Naltrexone / Q000031:analogs & derivatives / Q000494:pharmacology; D011388:Prolactin / Q000097:blood / Q000378:metabolism*; D011759:Pyrrolidines / Q000494:pharmacology; D051381:Rats; D017473:Receptors, Opioid, kappa / Q000502:physiology*; D012727:Sex Characteristics; D012737:Sex Factors; D013997:Time Factors; D000521:alpha-MSH / Q000378:metabolism*
D011759:Pyrrolidines; D017473:Receptors, Opioid, kappa; C051844:norbinaltorphimine; D000521:alpha-MSH; D009271:Naltrexone; D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; D011388:Prolactin