The Effect Of Electroacupuncture "Zusanli" On The Discharge Of ACC Neurons And Interstitial Cells Of Colon Cajal In IBS Model Rats

ObjectiveThis study observed the effect of electro-acupuncture at Zusanli(ST-36)on enteric sensitivity,emotional behavior,positive expression of c-kit receptor immunoreactants of interstitial cells of cajal and discharge of ACC neurons of rats with IBS,to study part of preventive and thera-peutical machnism of electro-acupuncture at Zusanli(ST-36)on physical and mental illness.MethodsWistar rats were randomly divided into blank control group(hereafter referred to as blank group)and model group.The model group were made for three-week maternal separation and two-week Acetic acid enema from second postnatal day,and colorectal distension when six-week.After the modeling,rats in the model group were randomly divided into model control group and Zusanli group,afterwards rats in each group were randomly assigned to implanting microelectrode in ACC,three of which for each group were ensured success.After a week of recovery,blank group and model control group subjected to no disposal,Zusanli group were disposed by electro-acupuncture at Zusanli(ST-36)once every other day for five times.Be-fore and after the treatment,enteric sensitivity,emotional behavior,the level of expression of c-kit immunoreactivity positive on interstitial cells of Cajal of colon and the change rule of discharge of ACC neurons of all groups were observed.Results1.Effect of electro-acupuncture at Zusanli(ST-36)on enteric sensitivity of rats with IBS Compared with blank group,latency and contract wave count of model group were signifi-cantly increased(P<0.05).Compared with model group,latency of Zusanli group were signi-ficantly increased and contract wave count of Zusanli group were significantly decreased(P<0.05).2.Effect of electro-acupuncture at Zusanli(ST-36)on emotional behavior of rats with IBS Compared with blank group,horizontal and vertical motion in 5min of model group were ex-tremely significantly decreased(P<0.01),horizontal and vertical motion in 10min of model group were also extremely significantly decreased(P<0.01).Compared with model group,Zusanli group have significantly increased horizontal motion in 5min(P<0.05).3.Effect of electro-acupuncture at Zusanli(ST-36)on the expression of c-kit immunoreacti-vity positive on interstitial cells of Cajal of colon of rats with IBSCompared with blank group,the expression of c-kit of model group remarkably increased(P<0.01).Compared with blank group,the expression of c-kit of Zusanli group significantly de-creased(P<0.05).4.Effect of electro-acupuncture at Zusanli(ST-36)on the discharge of ACC neurons of rats with IBSCompared with blank group,the mean discharge frequency of Unit A in ACC of model group significantly increased(P<0.01),while that of Unit B in ACC of model group significantly decreased(P<0.01).Compared with model group,the mean discharge frequency of Unit A in ACC of model group significantly decreased(P<0.01),while that of Unit B in ACC of model group significantly increased(P<0.01).Conclusions1.IBS model that were established by maternal separation,acetic acid enema and colorectal distension made higher enteric sensitivity and abnormal emotional behavior which was accor-dant with pathologic feature of IBS,which indicated that the IBS model was successful.2.Electro-acupuncture at Zusanli(ST-36)could improve the enteric hypersensitivity and emo-tional behavioral abnormality,which indicated that electro-acupuncture at Zusanli(ST-36)could restrain the pain reaction and relieve the emotional behavior abnormality.3.Electro-acupuncture at Zusanli(ST-36)could regulate the expression of c-kit immunereact-ivity positive on interstitial cells of Cajal of colon of rats,which indicated that the part of al-leviation machnism of electro-acupuncture at Zusanli(ST-36)on pain might be related to its regulation on interstitial cells of Cajal which contributed to reducing the enteric sensitivity.4.Except for improving the enteric hypersensitivity and emotional behavioral abnormality,Electro-acupuncture at Zusanli(ST-36)could also regularly change the firing rate of some types of neurons in ACC which might be involved in regulation of Zusanli(ST-36)on the affective pain of IBS rat.