Repeated injections of lipopolysaccharide attenuate the satiety effects of cholecystokinin.
The present study examined the effects of repeated injections of lipopolysaccharide (LPS) and cholecystokinin (CCK) on both sucrose palatability and body weight. Rats received repeated injections of LPS (200 microg/kg), CCK (8 microg/kg) and/or NaCl on days 1, 4, 7 and 10. Body weight was monitored on each test day and sucrose palatability was assessed using the taste reactivity test (TRT) on days 7 and 10. Rats treated with LPS developed a rapid tolerance to the reductions in body weight; however, this tolerance did not affect sucrose palatability. Furthermore it was found that repeated exposures to LPS and CCK attenuated the typical satiety related behaviors produced in the TRT by administration of CCK. This desensitization to CCK with repeated exposures to LPS may be one of the mechanisms that could account for the rapid development of tolerance to LPS-induced hypophagia.
Cross-Mellor
S K
SK
Neuroscience Program, University of Western Ontario, London, Canada.
Kavaliers
M
M
Ossenkopp
K P
KP
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002766:Cholecystokinin / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D004361:Drug Tolerance; D007267:Injections; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans; D012528:Satiety Response / Q000187:drug effects*; D013395:Sucrose; D013649:Taste / Q000187:drug effects; D013997:Time Factors
D008070:Lipopolysaccharides; D013395:Sucrose; D002766:Cholecystokinin