[Exercises at different intensities and sequential changes of rat skeletal muscle cell apoptosis].
OBJECTIVE
To study the effect of exercises of different intensities on rat skeletal muscle cell apoptosis.


METHODS
Rat models of exhaustive exercise-induced skeletal muscle injury was established using tread mill exercises at different speeds, and the skeletal muscle cell apoptosis was detected using propidium iodide (PI) staining and flow cytometry.


RESULTS
No obvious gastrocnemius cell apoptosis was observed in rats with normal exercise (P>0.05), but the cell apoptosis index was statistically significant in moderate and exhaustive exercise groups (P<0.05), reaching the highest level in exhaustive exercise group after exercising. The gastrocnemius cell apoptosis index increased obviously on days 1 and 3 of exercise, and stabilized in moderate and exhaustive exercise groups.


CONCLUSIONS
Exercises can evoke cell apoptosis and accelerate apoptotic cell clearance, and the imbalance between the two events during exercises may contribute to skeletal muscle injury.
Cai
Bao-ta
BT
Department of Orthopedics, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China. cbt3a@yahoo.com.cn
Yu
Bin
B
Zhao
Jiang-ping
JP
Zhang
Xing
X
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D005434:Flow Cytometry; D008297:Male; D018482:Muscle, Skeletal / Q000166:cytology / Q000503:physiopathology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors