Dual action of naloxone on feeding revealed by behavioural analysis: separate effects on initiation and termination of eating.
In two experiments observational analyses have been made of eating and other behaviours following naloxone administration. Naloxone produced a clearly defined profile of behavioural changes. Although rats became became more inactive it was demonstrated that this was not responsible for the inhibition of food intake. The drug reduced the latency to approach food and to initiate eating bouts. In addition, naloxone hastened the termination of eating in the test period. Therefore naloxone simultaneously increases one aspect of motivation for food, yet also promotes the onset of satiation. This profile of naloxone's anorexic action is quite different to that of traditional anorexic drugs such as amphetamine of fenfluramine. This dual action of naloxone, disclosed by these studies, may account for certain curious features of naloxone's effect on food intake.
D000818:Animals; D000855:Anorexia / Q000139:chemically induced; D004435:Eating / Q000187:drug effects*; D005247:Feeding Behavior / Q000187:drug effects*; D006120:Grooming / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009270:Naloxone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D009270:Naloxone