旋转床模拟推拉动作对脑循环功能的影响

目的 探讨推拉动作对脑血管循环功能的影响及推拉效应的＋ＧＺ下降机制。方法１０名被试者在旋转床上经受“直立位－倒立位－直立位”Ｒ 模拟推拉动作,采用网谱勒（ＴＣＤ）技术监测分析旋转床模拟推拉脑血流速度及脉动参数的变化。结果 倒立位时出现收缩期流速增加、舒张期流速降低、脉动参数ＰＩ与ＲＩ升高的阻力增高型频谱,随后直立位时,这些变化更加明显且恢复较慢。在实验过程中平均血流速度没有显著变化。结论在推拉动作

Effects of Rotating-table Simulated "Push-Pull Maneuver" on Cerebral Circulation Function

Objective: To investigate the change and regulation of cerebral circulation during rotating-table simulated push-pull maneuver. Method: A special rotating-table was used to simulate the push-pull maneuver. 10 healthy adults were subjected to a series of "head-up stand (+1Gz) 1 min head-down stand (-1Gz) 10 s and head-up stand (+1Gz) 1 min" changes. Cerebral blood flow velocity and pulsatility indices in the left middle cerebral artery were constantly measured with a TC2020TCD using Transcranial Doppler correction of Transcanial Dopplor] instrument. Result: During 10 s head-down stand (-1Gz) systolic velocity (Vs) increased, diastolic velocity (Vd) decreased, and the pulsatility indices (PI and RI) increased significantly in the left middle cerebral artery. During subsequent head-up stand (+1Gz), these changes didn't resume immediately and maintained for at least 20 s. Conclusion: This result implied that the push-pull maneuver increased the resistance of the cerebral vessels, which might be one of the mechanisms of the push-pull effect.