Central and peripheral catecholamines regulate the exercise-induced elevation of plasma interleukin 6 in rats

Several recent reports indicate that exercise elevates the plasma interleuk in 6 levels; however, the precise regulation of such an elevation still rem ains to be clarified. In this study, in order to clarify the requirements o f central and peripheral catecholaminergic system for this exercise-induced interleukin 6 elevation, rats were either intraperitoneally or intracerebr oventricularly injected with 6-hydroxydopamine which depletes the catechola mine in the central or peripheral tissues. As a result, our exercise protoc ol elevated the plasma interleukin 6, ACTH, and corticosterone levels in re sponse to exercise. All such exercise-induced increases in the interleukin 6, ACTH, and corticosterone levels were significantly inhibited by pretreat ment with an intracerebroventricular injection of 6-hydroxydopamine. In the intraperitoneal 6-hydroxydopamine-treated animals, the exercise-induced in terleukin 6 elevation was significantly suppressed compared with the vehicl e-treated animals, although no significant difference was found in either t he ACTH level or the corticosterone level between both groups of animals. T hese results thus suggest that central and peripheral catecholamines are in volved in the regulation of the exercise-induced interleukin 6 elevation. ( C) 2001 Elsevier Science Inc. All rights reserved.