Adverse effect of exercise on immune complex-mediated glomerulonephritis.

To assess the effect of strenuous daily exercise on immune complex-mediated glomerulonephritis (GN), rabbits were randomly assigned to one of three experimental groups: Group I (n = 12): treadmill exercise for 28 days plus twice weekly intravenous injections of saline. Group II (n = 10): treadmill exercise for 28 days plus twice weekly intravenous bovine serum albumin (BSA) injection. Group III (n = 9): intravenous doses of BSA, as in group II, but no exercise. Blood and urine samples were collected from each animal periodically during the 28-day experimental period. On the 29th day of the study all animals were sacrificed and tissue taken for renal histopathologic studies. We found that in group II (exercise + GN) abnormal albuminuria was more frequent (p less than 0.001), blood urea nitrogen (BUN) levels rose significantly with time (p less than 0.02) and hematuria (blood in renal tubules) was more common (p less than 0.05), compared to group III (GN only). The differences between groups II and III could not be explained by the effect of exercise alone since group I (exercise only) developed no abnormal albuminuria, BUN levels or hematuria during the course of the study. These findings suggest that strenuous exercise superimposed on active immune complex-mediated GN results in worsening of the abnormal glomerular function.