Research on Neiguan Acupoint Stimulation Against Cardiac Functional Changes in Simulated Weightlessness Rats

Abstract：Objective To research the effects of neiguan acupoint stimulation on the cardiac tunctional changes in simulated weightlessness rats and explore the new countermeasure against cardiac functional changes in weightlessness environment.Methods-30° tail suspended rats were used as the model to simulate the physiological effects of weightlessness.Wistar rats were randomly arranged into:control group(Con,n =10),tailsuspension group(TS,n =10) and TS + neiguan group(TS + neiguan,n =10).TS and TS + neiguan were suspended for 30 days,and TS + neiguan was yet stimulated in neiguan acupoint per two days.Results Compared with Con,the body weight in TS and TS + neiguan rats decreased significantly(P ＜ 0.05).About echocardiographic indexes:TS compared with Con,the interventricular septum of the end-diastole (IVSd),the interventricular septum of the end-systole(IVSs),fraction shortening(FS) and the left ventricular posterior wall of end-diastole(LVPWd) decreased (P ＜ 0.05),the left ventricular dimension of end-diastole (LVDd) and ejection fraction(EF) decreased significantly (P ＜ 0.01),the heart rate (HR) increased (P ＜ 0.05).TS + neiguan was the similar trend as TS but no significant difference as compared with Con,otherwise the LVDd increased very significantly(P ＜0.01) as compared with TS.It was showed neiguan stimulation ameliorating cardiac function of TS rats.Compared with Con and TS + neiguan rats,the noradrenaline (NE) and epinephrine(EPI) in TS increased significantly(P ＜0.01,P ＜0.05),as well as these indexes in the TS + neiguan rats had no statistical difference as compared with Con.There was no difference in angiotension Ⅱ (Ang Ⅱ) and corticosterone(CORT) among 3 groups.Compared with Con,serum aldosterone(ALD) concentration increased in TS (P ＜ 0.05) and TS + neiguan (P ＜ 0.01).Conclusion Simulated weightlessness mainly results in decrease of the left ventricular function,cardiac structural and cardiovascular regulatory changes,and neiguan acupoint stimulation may alleviate these disadvantageous influence and may have a good foreground in countermining the cardiac functional changes in weightlessness environment.