Stress and sucrose hyperphagia: role of endogenous opiates.
Two experimental situations induce hyperphagia in the rat: the cafeteria model and the tail-pinching model. In non-deprived rats which are offered for one hour a choice of 3 liquid cafeteria items in addition to ordinary chow and water, mild tail-pinching results in a preferential sucrose hyperphagia; naltrexone (2.5 mg/kg IP) suppresses this stress-induced hyperphagia; beta-endorphin (3 micrograms ICV) has the same effect. This apparent discrepancy is discussed: the antagonist may suppress the hyperphagia because it suppresses the reward provoked by the sucrose, the agonist because it makes it unnecessary.
D000818:Animals; D004723:Endorphins / Q000494:pharmacology / Q000502:physiology*; D001068:Feeding and Eating Disorders / Q000523:psychology*; D005502:Food; D005518:Food Preferences / Q000187:drug effects; D006801:Humans; D006963:Hyperphagia / Q000523:psychology*; D008297:Male; D009271:Naltrexone / Q000494:pharmacology; D009619:Nociceptors / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D013315:Stress, Psychological / Q000523:psychology*; D013395:Sucrose / Q000494:pharmacology*; D001615:beta-Endorphin
D004723:Endorphins; D013395:Sucrose; D009271:Naltrexone; D001615:beta-Endorphin