The effects of aging on day-night rhythms of Kappa opiate-mediated feeding in the mouse

✍ Scribed by Martin Kavaliers; G. Campbell Teskey; Maurice Hirst

• Publisher: Springer
• Year: 1985
• Tongue: English
• Weight: 688 KB
• Volume: 87
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00432709

✦ Synopsis

Day-night rhythms in feeding behavior and response to the specific kappa opioid agonist U-50,488H (0.10-10. mg/kg) were measured in young (1-2 months), mature (8-12 months) and old (24-30 months) male CF-1 mice. All the mice consumed more food at night than in the day-time, though this nocturnal peak was markedly reduced in old and mature animals. Young mice also displayed a significant, dose-related, nocturnal enhancement in U-50,488H-stimulated feeding. This day-night rhythm was reduced in mature animals and absent in old mice. In old mice, U-50,488H significantly stimulated feeding only after the high dose of 10 mg/kg. Additionally, old animals did not show the dose-dependent latency to initiation of feeding after administration which was observed in young mice and to a lesser extent in mature animals.