Interleukin-1beta-induced fever in young and old Long-Evans rats.
Aging is associated with a blunted or absent fever response to naturally occurring infections or to the peripheral administration of bacterial products and proinflammatory cytokines, including interleukin-1beta (IL-1beta). Whether old rats also exhibit an attenuated fever response when challenged with direct brain administration of IL-1beta is unknown. Here we investigated the fever response of young (3-5 mo) and old (24-26 mo) Long-Evans rats to the intracerebroventricular microinfusion of IL-1beta. Core body temperature was monitored by telemetry in freely moving rats. Intracerebroventricularly administered IL-1beta induced comparable increases in body temperature in young and old Long-Evans rats. In the two groups, IL-1beta-induced fever was similar both in latency to peak fever and maximal fever response, whether the cytokine was administered 2 h after lights on or just before lights off. These data show that old Long-Evans rats are not defective in their capacity to develop a fever in response to brain administration of IL-1beta.
Plata-Salamán
C R
CR
Department of Biological Sciences, University of Delaware, Newark, Delaware 19716-2590, USA.
Peloso
E
E
Satinoff
E
E
D000367:Age Factors; D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D002940:Circadian Rhythm; D005334:Fever / Q000139:chemically induced* / Q000276:immunology; D007276:Injections, Intraventricular; D007375:Interleukin-1 / Q000008:administration & dosage*; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans
D007375:Interleukin-1