A comparison of the effects of opiate antagonists on operant and ingestive behavior.
Previous studies have found that naloxone and other opiate antagonists will decrease the food and water intake of experimental animals. The present study investigated the possibility that these effects may be due to a generalized action of opiate antagonists to block an endogenous reward system. A direct comparison was made between the effects of naloxone and naltrexone on FR responding maintained by small quantities of milk and on the consumption of milk when it was freely available. Both drugs reduced milk consumption at all doses (0.3-30 mg/kg) but produced only small decreases in FR response rates at the highest doses. These results do not support the view that the actions of opiate antagonists on eating and drinking represent an inhibitory action on central reward mechanisms.
D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004326:Drinking / Q000187:drug effects*; D004435:Eating / Q000187:drug effects*; D008297:Male; D009270:Naloxone / Q000031:analogs & derivatives* / Q000494:pharmacology*; D009271:Naltrexone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D009270:Naloxone; D009271:Naltrexone