Giorli Elisa, Tognazzi Silvia, Briscese Lucia, Bocci Tommaso, Mazzatenta Andrea, Priori Alberto, Orlandi Giovanni, Del Sette Massimo, Sartucci Ferdinando
Department of Clinical and Experimental Medicine, Pisa University, Medical School, Pisa, Italy.
Department of Neuroscience, Neurology and Clinical Neurophysiology Section, University of Siena, Siena, Italy.
J Neuroimaging. 2015 Jul-Aug;25(4):571-4. doi: 10.1111/jon.12162. Epub 2014 Sep 26.
Cerebral vasomotor reserve (VMR) is the capability of cerebral arterioles to change their diameter in response to various stimuli, such hypercapnia. Changes of VMR due to transcranial direct current stimulation (tDCS) have been poorly studied.
Twenty-five healthy subjects underwent anodal/cathodal and sham tDCS on right primary motor area. Before and after tDCS, we assessed VMR by Transcranial Color-Coded Sonography (TCCS) calculating trought Breath Holding Index (BHI) and Heart Rate Variability (HRV), in particular after Valsalva manouver.
A-tDCS decreased VMR and BHI (p < 0.05), whereas C-tDCS increased VMR, and BHI (p < 0.05); Sham doesn't provide statistically significant of both VMR, BHI and HRV (p > 0.05).
Our study confirms that tDCS induces a modification of bilateral VMR with a polarity-specific effect; based on this bilateral MFV and BHI modifications, we can speculate an involvement of the SNS in the VMR regulation.
脑血管运动储备（VMR）是脑小动脉响应各种刺激（如高碳酸血症）而改变其直径的能力。经颅直流电刺激（tDCS）对VMR的影响研究较少。
25名健康受试者在右侧初级运动区接受阳极/阴极及假tDCS。在tDCS前后，我们通过经颅彩色编码超声（TCCS）评估VMR，计算屏气指数（BHI）和心率变异性（HRV），特别是在瓦尔萨尔瓦动作后。
阳极tDCS降低了VMR和BHI（p < 0.05），而阴极tDCS增加了VMR和BHI（p < 0.05）；假刺激对VMR、BHI和HRV均无统计学显著影响（p > 0.05）。
我们的研究证实tDCS可引起双侧VMR的改变，且具有极性特异性效应；基于双侧平均血流速度（MFV）和BHI的改变，我们推测交感神经系统参与了VMR的调节。
