We assessed the renal effects of chronic treadmill exercise in the remnant kidney model of chronic renal failure. Eight-week-old spontaneously hypertensive rats (SHR) were subjected to 5/6 nephrectomy by removal of the left kidney and infarction of two thirds of the right kidney . We performed two series of experiments. Firstly, we investigated the renal effects of chronic mild treadmill exercise in 5/6 nephrectomized SHR. The SHR were divided into 2 groups : a non-exercising group (Non-Ex) and a group conducting mild treadmill running at 20 m/min 0° grade for 30 min (Mild-Ex) 5 times/week for 4 weeks. Secondly, we investigated the effects of moderate or severe treadmill exercise in the rats. The SHR were divided into 3 groups : a non-exercising group (Non-Ex), a group conducting moderate treadmill running at 20 m/min 0° grade for 60 min (Moderate-Ex) and, a group conducting severe treadmill running at 35 m/min 0° grade for 60 min (Severe-Ex) 5 times/week for 4 weeks . Chronic treadmill exercise significantly attenuated the increase in proteinuria and serum total cholesterol levels intensity-dependently. These results were confirmed by morphological analysis of the kidneys. Moderate-Ex provided significantly effective protection against an increase in focal glomerular sclerosis . These results indicate that exercise did not worsen renal function and in contrast, suggest a renal-protective action in this rat model.
