Journal of Applied Physiology, Vol 78, Issue 2 458-465, Copyright © 1995 by American Physiological Society
Effect of exercise and food restriction on selected markers of the acute phase response in hamsters
C. A. Conn, W. E. Kozak, P. C. Tooten, T. A. Niewold, K. T. Borer and M. J. Kluger
Institute for Basic and Applied Medical Research, Lovelace Institutes, Albuquerque, New Mexico 87108, USA.
Acute aerobic exercise has been shown to elicit physiological changes
characteristic of the acute phase response (APR), a nonspecific host
defense response. Regular evocation of these changes may prime the immune
system to improve resistance to disease. Because food deprivation is
associated with an impaired APR, food restriction may prevent these
beneficial changes. We tested the hypotheses that voluntary exercise
elicits an APR and that food restriction modifies this response in four
groups of hamsters: ad libitum-fed sedentary, ad libitum-fed exercised,
food-restricted sedentary, and food-restricted exercised. Five variables
altered during an APR were examined: core temperature, serum iron, serum
interleukin-6, serum amyloid A, and serum glucocorticoids measured by
biotelemetry, colorimetric analysis, B-9 cell growth assay, indirect
enzyme-linked immunosorbent assay, and radioimmunoassay, respectively.
Blood was drawn during the hamsters' inactive period after 19-20 days of
access to running wheels. Resting core temperature was elevated by exercise
and depressed by food restriction (P < 0.01). Iron was depressed by food
restriction (P < 0.01). Cortisol, but not corticosterone, was elevated
by food restriction (P < 0.001). There were no significant differences
among groups in interleukin-6 (P > 0.49) or serum amyloid A (P >
0.29). We conclude that there is little evidence that voluntary exercise or
exercise combined with food restriction causes an APR in hamsters.
