Endurance exercise causes interaction among stress hormones, cytokines, neutrophil dynamics, and muscle damage. Suzuki, Katsuhiko, Manabu Totsuka, Shigeyuki Nakaji, Mutsuo Yamada, Satoru Kudoh, Qiang Liu, Kazuo Sugawara, Kanemitsu Yamaya, and Koki Sato. 1 Department of Hygiene, Hirosaki University School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan; 2 Department of Health and Physical Education, Faculty of Education, Hirosaki University, 1 Bunkyo-cho, Hirosaki, Aomori 036-8560, Japan; and 3 Oyokyo Kidney Research Institute, 90 Yamazaki, Kozawa, Hirosaki, Aomori 036-8243, Japan.
APStracts 6:0279A, 1999.
We analyzed adaptation mechanisms regulating systemic inflammatory response of the stressed body using an experimental challenge of repeated exercise bouts and accompanying muscle inflammation. Eight untrained men bicycled at 90 watts for 90 min 3 days in a row. Exercise induced peripheral neutrophilia with a left shift of neutrophil nucleus and neutrophil priming for oxidative activity determined by luminol-dependent chemiluminescence. Plasma growth hormone and interleukin 6 rose significantly following exercise, and were closely correlated with the neutrophil responses. Serum creatine kinase and myoglobin levels as muscle damage markers rose after exercise in delayed onset and were closely correlated with the preceding neutrophil responses. These exercise-induced responses were strongest on Day 1, but magnitude gradually decreased with progressive daily exercise. In contrast, the magnitude of catecholamine responses to exercise sessions gradually rose, possibly suppressing neutrophil oxidative responses. These results indicate that stress-induced systemic release of bioactive substances may determine neutrophil mobilization and functional status, which then may affect local tissue damage of susceptible organs.

Received 30 November 1998; accepted in final form 1 June 1999.
APS Manuscript Number A1085-8.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1999 The American Physiological Society.
Published in APStracts on 25 June 1999