Opioid and non-opioid components of insulin-induced feeding

• Published in: Pharmacology, biochemistry and behavior Vol. 24; no. 4; pp. 899 - 903
• Main Authors: Si, E.C.C., Bryant, H.U., Yim, G.K.W.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.04.1986; Elsevier Science
• Subjects: Animals; Applied sciences; Blood Glucose - analysis; Brain - physiology; Drug Interactions; Endogenous opioids; Endorphins - physiology; Exact sciences and technology; feeding behavior; Feeding Behavior - drug effects; Feeding Behavior - physiology; Food intake; Insulin; Insulin - administration & dosage; Male; Mice; Naloxone; Naloxone - administration & dosage; Naltrexone; Naltrexone - administration & dosage; opioids; Other techniques and industries; Endogenous opioids; Naloxone; Naltrexone; Food intake; Insulin
• ISSN: 0091-3057; 1873-5177
• DOI: 10.1016/0091-3057(86)90434-X

The present study was initiated to clarify the involvement of endogenous opioids in insulin-induced feeding. Naloxone (3 mg/kg) was injected in male Sprague Dawley rats every hour for 2 hours after insulin injection (10 U/kg). Only the first hour food intake was depressed (68% reduction). When naloxone was given only 1 hour after insulin administration, depression of food intake was not noted. When food was withheld for 2 hours after insulin injection, both naloxone and its long acting congener, naltrexone (3 mg/kg) were able to depress only the first hour feeding subsequent to food presentation. These data suggest that insulin-induced feeding can be divided into two pharmacologically distinct phases: the early phase being naloxone-sensitive while the late phase is naloxone-insensitive. Furthermore, the early phase begins with the presentation of food and not with the administration of insulin.