[Effects of chronic exercise on renal function in 5/6 nephrectomized spontaneously hypertensive rats (SHR)]

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 degree 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 degree grade for 60 min (Moderate-Ex) and, a group conducting severe treadmill running at 35 m/min 0 degree 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.