The Effects On Apoptosis And Bcl-2 Protein Expression Of Rat Kidney In Different Intensities Of Exercise

Objects: Overtraining can cause many organs dysfunction or injury including kidneys. How to prevent sports injury is a research focus in Sports Medicine. In this research we found a exercise model by swimming to compare pathological changes on rat kidney of different exercise. Immunohistochemistry was used to detect Bcl-2 expression protein in different group, application of TUNEL to detect rat renal cell apoptosis and discuss the mechanism of apoptosis to provide new ideas and theories for clinical diagnosis and treatment of training.Methods: 40 male Wistar rats were randomly divided into 3 groups. (1)control group: conventional breeding, not exercise; (2) general exercise groups: moderate intensity for swimming training, six days a week, once a day. (3) overload exercise groups: having the same environment to general exercise group, the training arrangements is the same to the general exercise group for the first two weeks, from the third week start weighting training, rear load from 1%-5% of the weight gradually but training time unchanged. From the fourth week, training increased one more time in the morning and the afternoon and, continued for eight weeks, 24 hours after the end training, 2%(40mg/kg)pentobarbital intraperitoneal anesthesia, conventional paraffin-embedded, making 5um kidney paraffin sections. HE staining of kidney to compare pathological changes, immunohistochemical detection of renal tissue Bcl-2 protein expression, TUNEL detection rat kidney cell apoptosis.Results: (1) general observation: the control group and the general exercise group are normal, overload group are easily noise,loss of hair,shape emaciated,eyes lackluster.(2) Pathological observation : In the control group, tubular structure is normal, in the interstitial edema without congestive. General exercise group mild glomerular enlargement,cysts area reduced. Overload exercise group tubular are sparse,disordered, kidney cysts disappeared, glomerular degeneration.(3) The results of immunohistochemistry: control group and the general exercise group, Bcl-2 in renal cell cytoplasm are obviously expression, compared to control group Bcl-2 protein expression was significantly increased in general exercise group, however, no significant difference (p >0.05).Compared to other groups Bcl-2 expression decreased significantly in overload group (p <0.05).(4) Apoptosis: there are less apoptosis expression in the control group and the general exercise group, in overload exercise group kidney cells cytoplasm have a large number of expression, the statistical results show that compared to control group the apoptosis significantly increased for overload exercise group(p<0.05).(5) Relation between the rate of apoptosis and expression of Bcl-2: statistical analysis showed that the correlation coefficient r=- 0.569 between the rate of apoptosis and Bcl-2 expression, associated probability p=0.001.Conclusion: (1) In general exercise group, glomerular mild swelling but there are not other clearly pathological changes. In overload exercise group, there are serious pathological changes. Tubular disarranged, renal cysts disappeared, glomerular degeneration. Tips for appropriate load will not produce damage, but overload can damage the kidneys. (2)There are certain Bcl-2 expression in normal group, compared to general exercise group, Bcl-2 protein expression increased, However, no significant difference.Compared to other groups, Bcl-2 expression decreased significantly in overload exercise group. Tips for appropriate load can make Bcl-2 protein expression increase, long term overload can make Bcl-2 protein expression reduced.(3)There are less apoptosis in normal exercise group, with the increase of exercise intensity, apoptosis increases, the expression of apoptosis are significantly different compared with other groups. Tips for apoptosis related to the load, apoptosis perhaps is one reasons for fatigue.(4) Apoptosis and Bcl-2 expression have significant negative correlation, However, there are more complex factors through more channels regulating apoptosis, and the mechanism need to be deeper study.