THE EFFECT OF VOLUNTARY WHEEL EXERCISE AND STRESS ON THE SPECIFIC ANTIBODY ANTIBODY RESPONSE

Abstract

121 Stressor modulates immune function, such that innate immune function is potentiated and adaptive (specific) immune function is suppressed. Acute stress suppresses the in vivo development of the specific antibody response. Voluntary exercise may buffer stress effects. Thus, we investigated the effect of voluntary wheel running on the stress-induced suppression of the specific antibody response. Each experiment (10/grp) contained 1). Exercise + stress, 2) Exercise + no stress, 3) Sedentary + stress, 3) Sedentary + no stress. Stress was exposure to tail shock (100, 5-s, 1.6mA, ave. ITI-60-s). Adult male Sprague-Dawley rats lived in cages with attached running wheels. Sedentary controls lived in identical cages, except the wheel was rendered inactive. In vivo specific immune function was assessed by immunizing the rats intraperitoneally with a benign soluble protein, keyhole limpet hemocyanin or KLH (200μg). Weekly blood samples were taken from the tail vein and serum anti-KLH IgM and IgG were measured using ELISA. Exp. 1-Rats were immunized with KLH and exposed to stress or remained in their home cage. Immediately after stress termination, rats were returned to their running wheel cages and allowed to run for 6 weeks. Exp. 2-This study was conducted just as exp. 1 except rats were allowed to live with running wheels (half active and half inactive) prior to exposure to stress. After 6 weeks, rats were immunized with KLH and exposed to stress or remained in their home cage. Blood samples were taken weekly for 6 weeks after KLH. The results from exp. 1 were that voluntary wheel running after stress exposure prevented the stress-induced suppression in anti-KLH IgM and IgG. Weekly average distance run was reduced by stress. The results from exp. 2 are not yet available. These data support to the hypothesis that voluntary activity protects against stress-induced immunosuppression.