振动锻炼和太空养心丸对60 d头低位卧床脑血流的影响

目的 通过观察和比较60 d头低位(HDT)卧床期间振动锻炼、中药太空养心丸对脑血流的影响,进一步明确不同对抗方式对失重不良影响的对抗效果. 方法 21名健康男性志愿者,随机分为对照组、振动组和中药组3组,每组7人.对照组仅-6°HDT卧床60 d,口服安慰剂;振动组和中药组在HDT卧床期间分别进行阻抗振动锻炼和口服太空养心丸.卧床前、卧床第30天、第60天测量右侧大脑中动脉的血流速度. 结果 对照组的收缩期血流速度(Vs)在卧床第30天较卧床前显著降低(t=3.44,P<0.05),并且在第60天进一步降低t=5.07,P<0.01);舒张期血流速度(Vd)、平均血流速度(Vm)在卧床第60天显著降低(t=2.61、7.20,P<0.05).振动组的Vs在卧床第30天显著降低(t=2.49,P<0.05),并且在卧床第60天进一步降低(t=3.49,P<0.01);中药组Vs、Vd和Vm有降低趋势,但未达显著水平. 结论 60d头低位卧床可引起大脑中动脉血流速度显著降低.卧床期间服用太空养心丸对改善脑血流有一定作用,而振动锻炼则对脑血流影响不大.

Effects of vibration training and Taikong Yangxin pill on cerebral blood flow during 60-day head-down tilt bed rest

Objective To investigate the effects of Chinese herb and vibration exercise on cerebral blood flow during 60d head-down tilt (HDT) bed rest. Methods Twenty-one healthy male subjects were randomly divided into control, vibration and Chinese herb groups, with 7 in each group.All of them were exposed to -6° HDT for 60 d. The subjects of control group took placebo while vibration group received vibration exercise and Chinese herb group took Taikong Yangxin pill.Cerebral blood flow velocity at right middle cerebral artery was respectively measured before HDT (supine), on day 30 and day 60 of HDT. Results In control group, peak systolic flow velocity (Vs)decreased significantly on the 30th day of HDT (t=3.44, P<0. 05), and decreased further on day 60of HDT (t=5.07, P<0. 01), and end diastolic flow velocity (Vd) and mean flow velocity (Vm) decreased significantly on day 60 of HDT (t = 2. 61, 7.20, P< 0. 05). In vibration group, Vs decreased significantly on day 30 of HDT (t= 2.49, P<0.05), and decreased further on day 60 of HDT (t=3. 49, P<0. 01). In the traditional Chinese drug group, Vs, Vd and Vm showed decreased tendercy but significant. Conclusions It's suggested that 60 d HDT may induce the reduction of cerebral blood flow velocity. Chinese herb could partially improve the cerebral blood flow during head-down tilt bed rest, but vibration exercise has no obvious effect on cerebral blood flow.