The Effect Of Long-term Swimming Exercise On Myocardial Cell Apoptosis In Juvenile Spontaneously Hypertensive Rats And Its Mechanism

Objective:The adult and old spontaneously hypertensive rats have abnormal apoptosis in cardiac muscle cells,long-term aerobic exercise can reduced the abnormal apoptosis of myocardial cells in adult and old SHR.But the early long-term swimming exercise had any effect on apoptosis ofmyocardial cells in young SHR,it has not yet been reported.In this study,we constructed the long-term aerobic exercise model to observe the effects of exercise on apoptosis of myocardial cells in young SHR.And analysis preliminary of its mechanism,in order to provide an animal experimental and theoretical evidence of exercise therapy for the patients with early hypertension.Methods:The experimental study used four-week-old male spontaneously hypertensive rats(SHR,n=20),and wistar kyota rats(WKY,n=9).SHR randomly divided into hypertension group(SHR,n=10)and trained hypertension group(SHR+E,n=10.Swimming six days a week,daily exercise 90mins).After 8 weks swimming exercise,removal of the heart tissue Partially preserved in formaldehyde make Paraffin sections for Tunel and immunohistochemistry,and Partially preserved in liquid nitrogen test protein bcl-2,bax,caspase-3 with western blot.Results:1.The results of apoptosis in spontaneously hypertension rats at myocardial c ells.In fluorescence microscopy 400 times can be observed that myocardial cella poptosis rate is obviously Spontaneously hypertensive rats in the control group c ompared with the normal control group(1.06667+0.02603)%VS(0.316667+0.01174,)%P<0.001.Spontaneously hypertensive rats in the exercise group compare d with spontaneously hypertensive rats in the control group apoptosis cells were reduced by swimming exercise(0.710+0.009661)%VS(1.066667%+0.02603)%,P<0.001.The results there was significant difference.2.The results of Immunohistochemistry,In fluorescence microscopy 400 times can be observed that Spontaneously hypertensive rats in the control group average optical density values compared with the normal control group rats the average optical density values of protein bcl-2 no significant,but average optical density values of protein bax and caspase-3 Increased.Spontaneously hypertensive rats in the exercise group compared with spontaneously hypertensive rats in the control group the average optical density values of protein bcl-2 increased,but bax and caspase-3 reduced.3.The results of western blot.Spontaneously hypertensive rats in the control group compared with the normal control group rats the expression of protein gray value bcl-2 no significant(P>0.05),protein bax and caspase-3 protein gray value reduced(p<0.05).Spontaneously hypertensive rats in the exercise group compared with spontaneously hypertensive rats in the control group the protein gray value of bcl-2 increased(P<0.05),but protein gray value of bax and caspase-3 reduced(P<0.05).Conclusions:1.Apoptosis of heart in young spontaneously hypertensive rats had significantly increasing.2.Long terms wimming exercise can inhibit the apoptosis rate of myocardial cells in youngSHR,the mechanism is probably through down regulation of Bax and Caspase-3,increase the expression of Bcl-2.