Hyperthermic effects of centrally injected (D-ala2, N-Me-Phe4, Met-(O)5-ol)-enkephalin (FK 33-824) in rabbits and guinea-pigs.
Intracerebroventricular administration of (D-ala2, N-Me-Phe4, Met-(O)5-ol)-enkephalin (FK 33-824) induced dose-related hyperthermia in rabbits and guinea-pigs. Prostaglandins (PG) and norepinephrine (NE) were not involved in the hyperthermia induced by FK 33-824 because a cyclooxygenase inhibitor, indomethacin, and an alpha-adrenoceptor antagonist, phenoxybenzamine, had no antagonistic effects. Likewise, cAMP was not required since a phosphodiesterase inhibitor, theophylline, did not accentuate the hyperthermia due to FK 33-824. It is suggested that mu receptors were involved in the induction of hyperthermia by FK 33-824 in rabbits and guinea-pigs since naloxone attenuated it. These results indicate that FK 33-824-induced hyperthermia is not mediated by PG, NE and cAMP, but rather that mu receptors are involved in the induction of hyperthermia by FK 33-824.
D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D000242:Cyclic AMP / Q000502:physiology; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin / Q000494:pharmacology*; D006168:Guinea Pigs; D007213:Indomethacin / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D009638:Norepinephrine / Q000502:physiology; D010643:Phenoxybenzamine / Q000494:pharmacology; D011453:Prostaglandins / Q000502:physiology; D011817:Rabbits; D013806:Theophylline / Q000494:pharmacology
D011453:Prostaglandins; D010643:Phenoxybenzamine; D009270:Naloxone; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D013806:Theophylline; D000242:Cyclic AMP; D009638:Norepinephrine; D007213:Indomethacin