The Study Of Jejunum Effects By Stimulating Different M Cho Linergic Mediated Receptors Using Electrical Stimulation

Objectives:The intestinal nervous system is an important pathway for acupuncture to regulate the jejunum movements. In this study, we use different amounts of electrical stimulation on 3 different groups of mice, namely the normal wild-type mice, M2M3 receptor knockout mice and M2 receptor knockout mice. This is to study the role of electrical stimulation of Muscarinic receptors (M receptors) which regulates intestinal movements as well as the effects of different amounts of electrical stimulation on intestinal movements.Methods:90 male mice were chosen, of which 30 were CL57/BL/6 wild-type mice,30 were M2M3 receptor knockout mice and 30 were M2 receptor knockout mice. A self-made water bursa which converts the amplitude and frequency of jejunum to intestinal pressure was placed in the mice intestines. The frequency of the electrical stimulation is set at 2/15Hz and the strength at 1mA、2mA、4mA、6mA and 8mA. Once the intestinal pressure is stabilized, the electrode is used to stimulate the 4 acupuncture points "Quchi", "Shangjuxu" "Tianshu" and "Dachangshu" respectively for 1 minute. The change in the frequency of jejunum movements before and after electrical stimulation were recorded and analysed.Results:(1) Overall, an electrical stimulation of "Quchi" and "Shangjuxu" increase the intestinal pressure while "Tianshu" and "Dachangshu" decrease the pressure.(2) The responses of electrical stimulation on intestinal movements were better in normal wild type mice than M2M3 receptor knockout mice and M2 receptor knockout mice.(3) For the wild type mice, when electrical stimulation increased from 1mA to 2mA, there is a statistical significant (P<0.05) increase in intestinal pressure. When the strength is 4mA、6mA and 8mA, there is an obvious statistical significant (P<0.01) increase in intestinal pressure. Concluding figure 1 to figure 4, the M2M3 receptor knockout group has a backward effect when compared with the normal wild type group after electrical stimulation of "Quchi" and "Shangjuxu" while the M2 receptor knockout group has a slow rising effect. The M2M3 receptor knockout group has a backward effect when compared with the normal wild type group after electrical stimulation of "Tianshu" and "Dachangshu" while the M2 receptor knockout group has a decreasingly increasing effect. After electrical stimulation of the M2M3 receptor knockout group at "Quchi" at 8mA and "Shangjuxu" at 6mA, the increase in intestinal pressure is statistically significant (P<0.05); electrical stimulation of "Tianshu" at 4mA showed obvious significance (P<0.01). However, there is no obvious significance at "Dachangshu".After electrical stimulation of the M2 receptor knockout group at "Quchi" at 4mA, the increase in intestinal pressure is statistically significant (P<0.05); electrical stimulation of "Quchi", "Shangjuxu" and "Tianshu" at 6mA showed obvious significance (P<0.01) respectively. While the electrical stimulation of "Dachangshu" at 6mA showed statistically significance (P<0.05) in the increase in intestinal pressure.Conclusion:(1) The regulation of acupuncture on jejunum movement is closely related with the autonomic nervous system. Acupuncture of "Quchi" and "Shangjuxu" can increase jejunum movements acupuncture while acupuncture of "Tianshu" and "Dachangshu" can inhibit jejunum movement, its mechanism is mainly by activating the sympathetic pathway. Dose-effect relationship exists.(2) The greater the intensity of electrical stimulation, the stronger the effect on the jejunum movements.(3) This dose-effect relationship is also closely linked with the M receptor, when M2M3 receptor is knockout, the electrical stimulation on jejunum movement is greatly affected.