目的:动态观察不同参数设置下的重复经颅磁刺激(r TMS)对正常大鼠脑局部皮质血流量变化的影响。方法:采用经颅磁刺激仪依次连续刺激Wistar大鼠右侧大脑皮质固定区域,根据刺激参数分为4组:高频高强度(5Hz,100%)组、高频低强度(5Hz,50%)组、低频高强度(1Hz,100%)组、低频低强度(1Hz,50%)组,每组参数刺激50次;通过激光多普勒血流仪记录激光探头下大鼠脑局部皮质血流量的变化。结果:4组不同参数r TMS干预后大鼠刺激区域脑皮质局部血流量均增高,不同强度的1Hz与5Hz经颅磁刺激后脑血流量曲线变化特征不同,强度是影响脑血流量变化的重要因素,频率与强度相互不影响,脑血流随刺激结束不再变化。结论:大鼠脑血流量变化呈强度依赖性,频率影响不明显,刺激后血流量变化无后续效应。
Objective: To observe the characteristics of cerebral blood flow(CBF) of normal rats in regional cortex affected by repetitive transcranial magnetic stimulation(rTMS) with different parameters dynamically. Method: Wistar rats were studied on fixed right cerebral cortex by transcranial magnetic stimulation(TMS). All rats were divided into four groups according to the stimulation parameters: high frequency and high strength (5Hz,100%), high frequency and low strength(5Hz,50%), low frequency and high strength(1Hz,100%), low frequency and low strength(1Hz,50%). Each group were stimulated for 50 times repeatedly. CBF were recorded by laser doppler blood flow meter dynamically. Result: Regional CBF of rats from four groups all increased after rTMS. Different intensities of rTMS of 1Hz and 5Hz could change CBF and the curves of CBF varied from different intensity and frequency combinations. After TMS CBF did not change. Conclusion: The CBF of rats by TMS were intensity-dependent. There was no interaction between intensity and strength and there was no subsequent effect after TMS.