经颅聚焦超声对脑缺血小鼠膈肌电活动的即时效应研究

关键词：经颅聚焦超声  脑卒中  膈肌电活动  前扣带回  神经调控

Keywords:transcranial focused ultrasound  stroke  diaphragmatic electrical activity  anterior cingulate cortex  neuromodulation

摘要：

      摘要 目的：探讨经颅聚焦超声（transcranial focused ultrasound， tFUS）无创调控前扣带回（anterior cingulate cortex， ACC）对卒中小鼠膈肌功能的即时效应，为卒中后呼吸功能康复提供一种新的神经调控策略。 方法：采用线栓法建立雄性C57BL/6J小鼠大脑中动脉栓塞（MCAO）再灌注模型，将造模成功的实验鼠随机分为120、140、160及180mVpp四个刺激强度组。利用经颅聚焦超声刺激患侧ACC区，并于刺激前后分别记录小鼠膈肌肌电信号，以膈肌电活动幅值的变化率作为评价指标。 结果：成功建立线栓法小鼠卒中后再灌注模型，经颅聚焦超声干预后，卒中模型小鼠膈肌肌电幅值较干预前显著升高（P<0.05）。各刺激强度组内左右两侧膈肌肌电幅值比较，差异无显著性意义（P>0.05）。不同刺激强度（120、140、160、180mVpp）组间比较，干预后膈肌幅值变化率无显著性差异（P>0.05）。 结论：经颅聚焦超声刺激前扣带回可即时增强卒中小鼠的膈肌电活动，提示tFUS改善卒中后呼吸功能障碍的潜力，但其剂量-效应关系尚不明确，需进一步研究。

Abstract:

      Abstract Objective: To investigate the immediate effects of non-invasive modulation of the anterior cingulate cortex (ACC) using transcranial focused ultrasound (tFUS) on diaphragmatic function in mice with stroke, and to provide a novel neuromodulation strategy for respiratory function rehabilitation after stroke. Method: A middle cerebral artery occlusion (MCAO) reperfusion model was established in male C57BL/6J mice using the suture method. Successfully modeled mice were randomly divided into four groups with different stimulation intensities: 120, 140, 160, and 180 mVpp. tFUS was applied to stimulate the ipsilateral ACC region. Diaphragmatic electromyography (EMG) signals were recorded before and after stimulation, and the rate of change in the amplitude of diaphragmatic electrical activity was used as the evaluation index. Result: The MCAO reperfusion mouse model was successfully established. After tFUS intervention, the amplitude of diaphragmatic EMG in the stroke model mice increased significantly compared with that before the intervention (P<0.05). There was no statistically significant difference in the amplitude of diaphragmatic EMG between the left and right sides within each stimulation intensity group (P>0.05). Comparison among the different stimulation intensity groups (120, 140, 160, and 180 mVpp) showed no significant difference in the rate of change of diaphragmatic EMG amplitude after the intervention (P>0.05). Conclusion: tFUS stimulation of the ACC can immediately enhance diaphragmatic electrical activity in stroke mice, suggesting the potential of tFUS for improving respiratory dysfunction after stroke. However, its dose-response relationship remains unclear and requires further investigation.