Physiological regulation of neurohypophyseal kappa-opiate receptors.
Quantitative autoradiography was used to examine the characteristics of kappa-opiate receptor binding in neural lobe sections from dehydrated rats and water-sated homozygous Brattleboro rats. The density of kappa-sites was decreased by 40% and 44%, respectively, after 5 days of water deprivation or hypertonic saline. Both the density and affinity of kappa-receptor sites were lower in homozygous Brattleboro rats. We suggest that kappa-receptor down-regulation occurs as a result of elevated release of opioid peptides induced by chronic osmotic stimulation.
D000700:Analgesics / Q000378:metabolism; D000818:Animals; D001575:Benzomorphans / Q000378:metabolism; D004399:Dynorphins / Q000494:pharmacology*; D005048:Etorphine / Q000378:metabolism; D006706:Homeostasis; D007700:Kinetics; D008297:Male; D010904:Pituitary Gland, Posterior / Q000502:physiology*; D051381:Rats; D011910:Rats, Brattleboro; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism*; D017473:Receptors, Opioid, kappa
D000700:Analgesics; D001575:Benzomorphans; D011957:Receptors, Opioid; D017473:Receptors, Opioid, kappa; D005048:Etorphine; D004399:Dynorphins; C027248:bremazocine