Fang Jun-Fan, Du Jun-Ying, Shao Xiao-Mei, Fang Jian-Qiao, Liu Zhe
Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, Zhejiang Province, 310053, China.
BMC Complement Altern Med. 2017 Mar 31;17(1):182. doi: 10.1186/s12906-017-1690-7.
The effect of electroacupuncture (EA) is affected by both the acupuncture point selection and the frequency of stimulation. However, little is known regarding acupuncture point and simulation frequency selection. Neuronal activation of the nucleus of the solitary tract (NTS) is one of the important targets of EA for modulating gastrointestinal function. This study investigated the effects of various combinations of EA frequencies and acupuncture points on NTS neurons.
Rats were randomly divided into normal, 2 Hz EA, 100 Hz EA and the alternate 2/100 Hz EA groups. Then rats in each group were randomly divided into the following two subgroups according to the acupuncture point: ST 36 group and ST 25 group. All the rats underwent electrode implantation surgery. Rats in all EA groups received one treatment with EA (a constant square wave at, 2 Hz,100 Hz or 2/100 Hz frequencies with intensities ranging from 1 to 2 mA), and NTS neuronal activation was recorded before and after EA treatment. Finally, to confirm the effect of EA on the NTS, minimal acupuncture was administered and its effect on NTS was detected.
ST 36 stimulated with 2 Hz EA significantly increased the population of excited NTS neurons and spike frequency. However, ST 36 stimulated with 100 Hz or 2/100 Hz EA produced only a transient effect on the activity of NTS neurons and did not induce any effect on the spike frequency. Furthermore, the excitatory effect of 100 Hz or 2/100 Hz EA on NTS neurons in the ST 36 group was lower than 2 Hz EA at the same point. When applied to ST 25, 2 Hz EA had no significant excitatory effect on NTS neurons or spike frequency. However, 100 Hz EA or 2/100 Hz EA at ST 25 decreased both NTS neuronal excitability and spike frequency. By comparing the effects of different EA combinations, it was shown 2 Hz EA applied to ST 36 had the strongest excitatory effect on NTS neurons, while 100 Hz EA applied to ST 25 had the greatest inhibitory effect. Minimal acupuncture stimulation produced no effect on NTS neurons.
EA's effects on NTS were mainly affected by the acupuncture point selection, but the frequency of EA also played a role. Different combinations of acupuncture points and frequency selection may lead to different EA effects on NTS neuronal excitability.
电针（EA）的效果受穴位选择和刺激频率两者影响。然而，关于穴位和刺激频率的选择知之甚少。孤束核（NTS）的神经元激活是电针调节胃肠功能的重要靶点之一。本研究探讨了电针频率和穴位的不同组合对NTS神经元的影响。
将大鼠随机分为正常组、2Hz电针组、100Hz电针组和2/100Hz交替电针组。然后根据穴位将每组大鼠随机分为以下两个亚组：足三里组和天枢组。所有大鼠均接受电极植入手术。所有电针组大鼠接受一次电针治疗（频率为2Hz、100Hz或2/100Hz的恒定方波，强度为1至2mA），并在电针治疗前后记录NTS神经元激活情况。最后，为证实电针对NTS的作用，给予最小针刺并检测其对NTS的作用。
2Hz电针刺激足三里可显著增加兴奋的NTS神经元数量和放电频率。然而，100Hz或2/100Hz电针刺激足三里对NTS神经元的活动仅产生短暂影响，且对放电频率无任何影响。此外，100Hz或2/100Hz电针刺激足三里组中NTS神经元的兴奋作用低于同一点的2Hz电针。当应用于天枢时，2Hz电针对NTS神经元或放电频率无明显兴奋作用。然而，天枢处的100Hz电针或2/100Hz电针可降低NTS神经元兴奋性和放电频率。通过比较不同电针组合的效果，结果显示，应用于足三里的2Hz电针对NTS神经元的兴奋作用最强，而应用于天枢的100Hz电针具有最大抑制作用。最小针刺刺激对NTS神经元无作用。
电针对NTS的作用主要受穴位选择影响，但电针频率也起作用。穴位和频率选择的不同组合可能导致电针对NTS神经元兴奋性产生不同影响。
