Electroacupuncture at ST-36 relieves visceral hypersensitivity and decreases 5-HT(3) receptor level in the colon in chronic visceral hypersensitivity rats.
OBJECTIVE
Visceral hypersensitivity is an important pathological mechanism of irritable bowel syndrome. Electroacupuncture (EA) could relieve chronic visceral hypersensitivity (CVH) in rats. However, little information is available about the mechanism. The aim of this study was to confirm the effects of EA at acupoint ST-36 (Zusanli) on CVH induced by the chemical colorectal irritation during postnatal development of rats, and to explore the possible 5-HT(3) receptor mechanism.


METHODS
Rats were randomized into four groups, including the normal control group, CVH group, CVH with EA group, and CVH with sham EA group. The abdominal electromyogram (EMG) in response to colorectal distension was selected as the index for measurement of visceral hypersensitivity. 5-HT(3) receptors were analyzed through reverse transcription-polymerase chain reaction and western blot.


RESULTS
EA at ST-36 significantly decreased evoked EMG. The expression of 5-HT(3) receptor in the colon was increased in rats with CVH, and decreased after EA treatment.


CONCLUSIONS
EA at acupoint ST-36 attenuates CVH in rats and decreases 5-HT(3) receptor level in the colon. Decreased 5-HT(3) receptor level in the colon may mediate the beneficial effect of EA in rats with CVH.
Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jie Fang Road, Wuhan, Hubei, China 430022.
Dan
D
Chu
Pengfei
P
Cheng
Huiling
H
Xiong
Junjun
J
Zhang
Shi
S
Liu
Xiaohua
X
Hou
D015669:Acupuncture Points; D000818:Animals; D002908:Chronic Disease; D003106:Colon / Q000378:metabolism*; D015671:Electroacupuncture; D004576:Electromyography; D005786:Gene Expression Regulation; D006967:Hypersensitivity / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D044406:Receptors, Serotonin, 5-HT3 / Q000235:genetics / Q000378:metabolism*; D014781:Viscera / Q000473:pathology* / Q000503:physiopathology
D012333:RNA, Messenger; D044406:Receptors, Serotonin, 5-HT3