Effects Of Exhaustive Exercise And Blunt Contusion On Proliferation And Hes1 / Jagged1 / Pax7 Contents In Skeletal Muscle Satellite Cells In

Experiment objectiveThe purpose of this paper was to investigated the effects of one-time exhaustive exercise and contusion on the proliferation in vitro of skeletal muscle satellite cells and the contents of Hesl/Jagged 1/Pax7 in rat.Methods42 SD male rats were randomly divided into seven groups (n=6):control group (C),instantly exhaustive exercise group(EO), group of 24hour after exhaustive exercise (E24), group of 48hour after exhaustive exercise (E48), instantly contusion group(DO), group of 24hour after contusion (D24), group of 48hour after contusion (D48).The exhaustive exercise groups were given disposable treadmill exhaustive exercise.A11 of the exhaustive exercise groups and the control group were anesthetized by twenty percents urethan and killed at different time points after the last exhaustive exercise and in a quiet state.The serum was taken and the gastrocnemius was divided into two.One of them was used to cell culture experiments at once,the other was kept in storage with liquid nitrogen which was detected the changes of Hesl/Jagged1/Pax7 content by ELISA. In addition,the left gastrocnemius from a newborn rat was also taken for cell culture experiments.Experiment results(1) The result of muscle cell culture:Highly purified satellite cells with potential of muscle regeneration could be acquired in vitro by digestion and separation of rat muscle.At the incipient stage, the proliferation of the muscle satellite cell in the newborn group was faster than other groups. The spindle cells can be seen at the next day of culture and proliferated significantly at the fouth and fifth day. They covered the most Petri dish with a peak at the seven day, then the growth of muscle satellite cells became slow down. On the other hand, the speed of proliferation in Control was slowest, and the one in exhaustive exercise groups and in contusion groups were between newborn group and control group.The proliferation of contusion groups was faster than that of exhaustive exercise groups.(2)The results of ELISA:Compared with the control group,the contents of Hesl/Jagged1/Pax7 in skeletal muscle and the serum increased significantly in Exhaustive exercise groups and contusion groups (P＜0.05). There were no significant change among these exhaustive exercise groups, and EO were a little lower than E24 and E48. On the other hand, the contents of Hesl/Jagged1/Pax7 in skeletal muscle and the serum in Contusion groups had a same trend compared by exhaustive exercise groups.Conclusion(1)There was no obvious proliferation of muscle satellite cells in control group. The skeletal muscle satellite cells can be activated and increased by the exhaustive exercise and contusion,and the activation of contusion was stronger than the exhaustive exercise.(2)The contents of Hes1, Jagged1, Pax7 in skeletal muscle and serum were significantly increased in the exhaustive exercise groups and contusion groups compared with control group, and the values of exhaustive exercise groups was lower than those of contusion groups. As we know, exhaustive exercise and contusion both can make Hesl/Jagged1/Pax7 up in rat’s skeletal muscle which may be play a positive regulating role in skeletal muscle satellite cell activation and skeletal muscle injury and repair.