Peripheral Nerve Discharge Elicited by Manual Acupuncture at Zusanli (ST 36) Regulates Blood Pressure in Anesthetized Rats

目的:麻醉状态下观察手针大鼠后肢足三里穴位引起的支配该穴区的特异性神经束放电以及由此诱发的相应靶器官血压波动效应。方法:将水合氯醛麻醉处理的雄性大鼠随机分为针刺组、利多卡因注射后针刺组(穴位邻近区域肌肉注射2%利多卡因后进行足三里手针刺激)并设生理盐水注射后针刺组(穴位邻近区域肌肉注射生理盐水后进行足三里手针刺激)作为对照。持续记录足三里针剌过程中大鼠右颈动脉血压变化并同对记录分析相应的神经柬放电情况。结果:以一定手法手针大鼠足三里能够引起明显的特异性神经束放电并引起相应动脉血压的下降(P<0.05),而在穴位邻近区域注射利多卡因后上述现象消失。结论:手针大鼠足三里能够诱发支配穴位的特异性外周神经放电,该神经信号可能通过躯体心血管反射参与调节体内的血压变化。

Objective： To investigate target organ response by recording mean arterial blood pressure （MAP） fluctuation corresponding to nerve-tract discharges from the nerve innervating acupoint of Zusanli （ST 36） in the hind limb evoked by MA in anesthetized rats. Methods： Male SD rats anesthetized with chloral hydrate were randomly divided into 3 groups which were treated with manual acupuncture （MA）, injection of lidocaine followed by MA and injection of normal saline （NS） followed by MA, respectively. The right carotid artery was canulated for persistent measurement of the blood pressure and meanwhile nerve discharges from the nerve-tract were recorded for analysis with amplitude spike counts for every 5 s. Results： The results showed that there were significant nerve discharges recorded from the nerve-tract when applying MA at Zusanli （ST 36） and simultaneous decrease in the MAP, while there was no response when inserting a needle into the Zusanli （ST 36） without manipulation （P〈0.05）. Furthermore, the reduction of MAP during MA could be completely abolished after blockade of peripheral nerve discharges with an injection of lidocaine into the tissue around Zusanli （ST 36） but not with that of normal saline （NS）. Conclusion： These results indicate that MA at Zusanli （ST 36） can elicit the peripheral nerve discharges from the nerve innervating the acupoint; such kind of nerve discharges may contain acupuncture signal regulating blood pressure via somato-cardiovascular reflex.