Long-term Aerobic Exercise For Heart Failure Rats Effects Of Nerve Growth Factor Expression

Objective: The purpose of this study was to discuss the effect of aerobic exerciseon NGF expression in cardiac sympathetic, through the long-term aerobic training ofWistar rats suffered from heart failure. So that to develop new therapeutic strategiesfor patients with failure.Method:80clean male Wistar rat were chosen in the study, ligated their Coronaryto establish models of heart failure after myocardial infarction. Then the80rats weredivided into two groups—MI (Myocardial infarction) Group and Sham Group, furtherinto four groups—Sham Group (Sham), Sham Exercise Group (Sham&E),Myocardial Infarction Group (MI) and Myocardial Infarction Exercise Group (MI&E).Four weeks after myocardial infarction surgery, a echocardiography was performedon the MI Group. The rat would be a HE object of study if LVEF≤45％. Sham&Eand MI&E groups would be chosen to do treadmill exercise for10weeks, Sham andMI groups would keep in quiet state. Finally, the sample sizes were respectively10inSham Group,10in Sham&E Group,10in MI Group and9in MI&E Group. Twodays after the ten-week’s exercise, weighed the rats, investigated venous blood,plasma and myocardial, then measured the content of NGF and mRNA byfluorescence quantitative and the content of NGF protein by Western blot.Result:(1) Weight: before the treadmill exercise, there was almost no differencebetween two groups; ten weeks later, the ranks of weights were MI&E, Sham&E, MIand Sham (MI&E was the heaviest group).(2) The changes of plasma NE andmyocardial NE: after ten-weeks aerobic exercise, the changes of plasma NE andmyocardial NE were very similar. That is to say,their contents were much higher inMI Group than those in Sham and MI&E Groups(P<0.01). Compared to Sham Group,Sham&E and MI&E Groups were almost the same with before (P>0.05).(3) Changesof sympathetic ganglion and myocardial NGF mRNA: the content of sympatheticganglion NGF mRNA in MI Group was much lower than that in Sham Group and MI&E Group(P<0.01); Sham&E and MI&E Groups were almost the same with before (P>0.05). the content of NGF mRNA in MI Group was much lower than that in ShamGroup and MI&E Group(P<0.01); Sham&E and MI&E Groups were almost the samewith before (P>0.05).（4）Changes of myocardial NGF protein, compared to ShamGroup and MI&E Group, myocardial NGF protein was lower in MI Group(P<0.01);myocardial NGF protein was dramatically lower in MI&E Group than that in ShamGroup (P>0.05).Conclusion:（1）Long-term aerobic exercise would increase heart weight and heartweight/body weight,thus promot cardiac remodeling.（2）Long-term aerobic exercise would reduce the release ofperipheral sympathetic ganglia.（3）Long-term aerobic exercise would increase expression ofsympathetic neurons.（4）Long-term aerobic exercise could adjust the hyper excitabilitystate of sympathetic, thus improve exercise endurance.