The Research About The Effects Of Overtraining And Dansheng Injection On Cardiac Muscle Apoptosis In Rats

Objective: It's told by available information that apoptosis exists in the physiological and pathological processes of the body, such as heart development, body movement and disease development and so on. However, the mechanism of apoptosis is not yet clear. This study, in an attempt to study SD rats'myocardial apoptosis'characteristics and regularities of occurrence, development and changes in chronic exhaustive exercise, tries to get evidence whether exercise load is associated with the existence of apoptosis, and to explore further the myocardial apoptosis mechanism caused by exercise as well. This study can also offer theoretical basis for the study of exercise training and monitoring in the future.Methods:110 10-week-old healthy male Sprague-Dawley rats were randomly divided into quiet comparision group (n = 10) and repeated exhaustive exercise group (n=50) and Danshen injection group(n=50).And then the repeated group and Danshen injection group were randomly divided into five groups (n=10):immediate,6h after exercise,24h after exercise,48h and 72h. The exercise lasted 3 weeks. Each exercise started at 5m/min,and was increased gradually to 30m/min within 10min with gradient 0o(degree). Then this speed was maintained until the rats exhausted .The rats in three groups were killed respectively in a quiet state and immediately after exercise,6h after exercise,24h,48h and 72h respectively The serum were made by the blood from the hearts and paraffin by the myocardium of rats .The structural changes of the nucleus of apoptosis myocardial cells were observed under the fluorescence microscope at 40×10 times after the paraffin being TUNEL marked.The experimental results: (1) scattered TUNEL-positive cardiac cell nucleus could be occasionally found in the quiet control group, and clear apoptotic nuclei could be detected in the repeated exhaustive group, whose myocardial apoptosis index is significantly higher than that of the quiet control group .And withering-death index difference between the two groups was statistically significant (p<0.05).(2) Observed under a microscope the shapes of the nucleus of apoptotic cells changed irregularly; chromatin converged at the edge of nuclear membrane; the intactness of mitochondrial'inside and outside membrane was destroyed, with vacuoles appearing; and the structure of cell membrane and nuclear membrane was destroyed. (3) compared with the quiet control group, the myocardium SOD activity of the rats in the repeated exhaustive exercise group went down a lot, with significant difference (p<0.05), but Danshen injection group change a litter,(4) after repeated exhaustive exercise, the calcium content in the myocardial mitochondrial of the rats in the exhaustive exercise group increased more significantly than that of the quiet control group (P<0.05), with a significant difference between, the calcium content in the myocardial mitochondrial of the rats in Danshen injection group increased no significantly,Conclusion: The repeated exhaustive exercise can lead to myocardial apoptosis, and moderate-intensity exhaustive exercise maybe cause myocardial apoptosis more easily. Perhaps there is a close relationship between the intensity and duration of the exhaustive exercise. The possible mechanism of myocardial cell apoptosis is due to that the huge accumulation of Ca2+ in mitochondrial causes apoptosis. Dansheng injection can decrease myocardial apoptosis induced by overtraining in rats,the medicine can be used as to decrease myocardial apoptosis.