Hyperthermia in the rat from handling stress blocked by naltrexone injected into the preoptic-anterior hypothalamus.
Experimental handling and colonic temperature measurement have been shown to cause stress and induce a long-lasting rise in colonic temperature in the rat. This stress-induced hyperthermia was blocked by microinjection of the narcotic antagonist naltrexone into the preoptic-anterior hypothalamus (POAH) of the brain, but was not significantly affected by similar injections into areas of the brain above the POAH. Thus, the stress-induced hyperthermia may be caused by activation of the endogenous opioid mechanism in the POAH.
D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D001921:Brain; D006234:Handling, Psychological / Q000502:physiology*; D006801:Humans; D007026:Hypothalamic Area, Lateral; D007032:Hypothalamus, Anterior; D007267:Injections; D007274:Injections, Intraperitoneal; D008297:Male; D009270:Naloxone / Q000031:analogs & derivatives*; D009271:Naltrexone / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013315:Stress, Psychological / Q000503:physiopathology*
D009270:Naloxone; D009271:Naltrexone