ABSTRACT
Objective To investigate the protective effects of Digoxin on cardioventricular function in rats after simulated weightlessness.Methods Eighty rats were divided randomly into 5 groups:control(Con)group,tail-suspended+sham feeding(TS+SF)group,tail-suspended+Digoxin 2 wk(TS+D2)group and tail-suspended+Digoxin 3 wk(TS+D3)group.The TS+SF group was given the distilled water.At the end of tail-suspended for 3 weeks,the heart function of 10 rats in each group was examined with echocardiography.The level of atrial natriuretic polypeptide(ANP)in serum was measured with immunoradiometric assay in other 6 rats.Results Compared with TS+SF group,the contractile function of LV improved in TS+D2 and TS+D3 groups(P0.05).Conclusion Digoxin can improve muscle contractile and blood ejection of LV and retard the tendency of atrophy in simulated weightlessness.
ABSTRACT
Objective To establish a carrying system for space cellular experiment suitable for astronaut to carry out cellular experiments on Shenzhou-6 mission.Methods The cell carrying sample bag,sample box and sample box integrated package were designed.Primary cardiomyocytes and osteoblasts culture and ground model experiment in the simulated environment of space cabin were performed.With man-tended,the cellular experiment was carried out on the orbit.Results After 5 d space flight,the returned cell samples were analyzed.The results demonstrated that the system was of good safety,reliability and applicability,as well as satisfied the demands of analyzed samples.Conclusion After Shenzhou-6 space flight,it is showed that this system fits for small loading,multi-cells and man-tended carrying mission,and can satisfy the demand of the first man-tended space cellular experiments carried out on the Shenzhou-6 spacecraft.