Central Mechanism Of Colon Movement Study On Treating Diarrhea Model Rats By Acupuncture Treatment On Zusanli And Quchi

ObjectiveThe theory of meridian-organ relationships is a core in Traditional Chinese Medicine (TCM). There are more classical books of TCM emphasize the relationship of organs issues with the 12 meridians. The goal of this study was to investigate the effects of acupuncture points on colonic contraction using an inflammation rat model. There are many papers reported that "Zu San Li",ST36, it is the most effective acupuncture point to treat the both constipation patients or diarrhea patients in the TCM system. However, the mechanisms of those treatments on using acupuncture are still not clear. In this study the regulation mechanisms in central never system was investigated especially to the vago-vagal reflex related transmitters like glutamate and GABA.MethodsThere were 56 male Sprague-Dawley rats have been used in this study. The animals had been randomly divided into two groups, diarrhea model group and control group. Colitis was induced by intracolonic instillation of 4% acetic acid in diarrhea model group and the control group was using same method by intracolonic instillation of normal salt solution. The extent of inflammation was assessed by histological examination and myeloperoxidase (MPO) activity assay .The experiments were conducted in the 2nd day of intracolonic instillation. A new localized perfusion recoding method for in-vivo colonic contraction was developed in this study. Electrical acupuncture on ST36 and manually acupuncture LI11 (Qu Chi) were used in this study for either 30 min or 15 min. Also a M2 agonist induced GMC has been investigated in this study as well. For studying on effect of vagal afferent function in vago-vagal reflexes TTX has been used in the perfusion solution. Also the intra ventricle microinject has been used to apply the antagonists of glutamate or GABA, and HPLC has been used in this study to measure the concentrations of glutamate and GABA in the brain steam.Results1.The recording of colonic contruction in vivo with localized chamber perfusion is a new and effective way on the colonic motility researches especially for the small animal like rats.2.In the 2nd day of intracolonic instillation, the inflamed model group revealed the diarrhea and their MPO increased the inflamed model group (p<0.01)3.In the inflamed the proximal rat colon, the phasic contraction and tonic contraction were depressed (p<0.05) with a super sensitivity to agonist agents, and sometime the GMC contraction pattern was revealed.4.Electrical acupuncture ST36 increased the colonic contraction for both control (P<0.05) and diarrhea (P<0.05) groups, but the effects was more stronger to diarrhea group (p<0.05) than control group. Acupuncture LI11 did not show the some results.5.Before acupuncture ST36, microinject kynurenic acid, a glutamate antagonist, in brain ventricle can decrease (p<0.05) the effects of acupuncture ST36.6.In diarrhea group, the reaction to M2 agonist was increased then control group (p<0.05). 7.using twice M2 agonist perfusion method to simulate the GMC attacks in diarrhea, acupuncture ST36 and LI11 did not affect the first time M2 agonist perfusion induced colonic GMC's like contractions, but decreased the following M2 agonist perfusion induced colonic contractions (P<0.05) in diarrhea group.8.Using TTX(10^-6M) in the perfusion chamber blocked above effect to the 2nd M2 agonist perfusion to the diarrhea group.9.Brain ventricle micro injection of Flucybene can partially block decreasing effects of the 2nd M2 agonist perfusion to the diarrhea group (p<0.05).10.Acupuncture ST36 increased glutamate and after first M2 agonist perfusion using acupuncture ST36 and LI11 increased GABA in brain steam in HPLC tastings.Conclusion1.The recording of colonic contruction in vivo with localized chamber perfusion is a new and effective way on the colonic motility researches especial for the small animal like rats.2.In the inflamed the proximal rat colon, the phasic contraction and tonic contraction were depressed and sometime the GMC contraction pattern was revealed.3.Acupuncture LI11 did not affect the colonic contraction, but acupuncture ST36 increased the colonic contraction (p<0.05) especial in the diarrhea group and adding LI11 increased the effects (p<0.05), it indicated that group using acupuncture points will be more effective to the treatments.4.The strong contraction in GMT through the GI wall sensor and vagal afferent fiber to sending the information into central never system, so that GABA increased to regulate colonic contraction and colitis can enforce this effects. 5.Acupuncture ST36 increases colonic contractions but no effect by acupuncture LI11 along. Acupuncture ST36 increases glutamate in the brain stream that does not need any other mediators, but acupuncture ST36 increases GABA in the brain steam seems require other mediators. These results might explain the acupuncture ST36 can have dual effects on the GI motilities.6.Acupuncture ST36 and LI11 to treat diarrhea could be by the vagal afferent information from strong GMC in the colon to facilitate the central never system to initiate the regulation to the colonic motility by increasing GABA, and colitis condition might be required for this change or as a helper for this central never regulation to the colonic motility. Even this study indicates the central never system mechanisms of acupuncture, but more detail investigation is still need to fully understand the functions of acupuncture treatments to GI motility.