The Effect Of Exercise On Myocardial Jak2 And Stat5 Expression

Objective To explore the role of exercise-induced changes in myocardial function in the process, as well as the impact of the exercise, we observe the expression of the member of IL-6 (interleukin-6) family, JAK2(janus kinases-2) and STAT5(signal transducers and activators of transcription-5) in myocardial of left ventricular after exercise.Methods We selected 51 male SD rats for acute exercise and then they were randomly divided into a control group and an acute exercise training group. The acute exercise training group was divided into 0 hours,1 hours,3 hours,5 hours 12 hours and 24 hours after exercise. The rats control group were just lived a normal life in cage and the acute exercise training groups were trained on the treadmill which refered to the Bedford increasing load model.51 SD male rats for long-term endurance exercise model, and they were divided into a control group and six endurance exercise groups such as 0 hours,1 hours,3 hours,5 hours,12 hours,24 hours after exercise. After 3 days adaptation, and we used the exercise program which refers to the Bedford increasing load treadmill and long-term endurance treadmill model planned by Wang Yunhong. The exercise groups were trained 6 days rest 1 day every week for 10 weeks. The control group stayed in cages quietly. there were three stages in the entire training cycle:From 1s1 to 4th week was speed-up and time-up stage; from 5th to 7th week was slope-up stage; from 8th to 10th was speed-up stage.The rats were killed after the last training according to the schedule time. Following we drew blood from abdominal aorta and took out the heart and weighed immediately. Remove the apex of heart about 1×1×1 mm3 and fixed by glutaraldehyde which were ready for electrical microscope slice. At last, we took out the left ventricular myocardium, then fixed, dehydrated, waxed, embedded, and sliced. They are used in the conventional HE and immunohistochemistry detection. The data collected was analyzed with SPSS 13.0.Results In acute exercise, the positive expression rate of p-STAT5 increased in 1 hours and 3 hours compared with the 24 hours. The average gray value of p-JAK2 increased in 24 hours compared with control group,0 hours and 1 hours.Conclusions 1.There was mild damage on myocardium in 1 hours,3 hours,5 hours after acute exercise. There was partially recovered in 12 hours and basically recovered in 24 hours. There were adaptive changes and minor pathological changes happened to myocardium of the long-term endurance exercise groups.2. After the IL-6 receptor aggregated into homologous heterodimer, the JAK2 was activated, so that the expression of JAK2 increased. At the first, the expression of p-JAK2 after exercise decreased (1 hour after exercise), as the movement of the stop and then increased (3 hours after exercise), and the difference was significant.3. The JAK2 activated STAT5 further more, showing that the expression of p-STAT5 increased. This indicating that the effect of exercise on myocardial function JAK2/STAT5 signaling pathway involved in.4. In the long-term endurance model, the expression of p-STAT5 in the exercise groups tended to increase but no significantly difference. The SOCS2 decreased after exercise and decreased to the bottom in 5 hours(P<0.05). This suggests that, the inhibitory effect of SOCS2 weakened after exercise and the STAT5 activated. They may be participated in the signal ing-transduction pathway of cardiac hypertrophy.