LU Yuan, GU Muen, LI Han, HUANG Yan, ZHOU Cili, WU Huangan, DONG Yongzheng, SHI Zheng, DING Guanghong, BAO Chunhui, FENG Xiaoming, WU Luyi

(1.  Department  of  Mechanics  and  Engineering  Science,  Fudan  University.  Shanghai  200433,  China.;  2.Shanghai  Institute  of  Acupuncture-Moxibustion  and  Meridian.  Shanghai  200030,  China.;  3.  Shanghai University of Traditional Chinese Medicine. Shanghai  201203, China.;  4. Shanghai Qigong  Research Institute, 

Shanghai University of Traditional Chinese Medicine, Shanghai 200030, China.)

Abstract:  Objective:  To  further  explore  the  mechanisms  of  warming  moxibustion  on  irritable  bowel syndrome (IBS). Methods: 24 male Sprague-Dawley (SD) rats were randomly divided into 3 groups: normal group, IBS group, and warming moxibustion group (WM group). Rats in the WM group received moxibustion at  Tianshu  acupoints  (ST25)  for  20  min  once  per  day.  A  total  of  7  treatments  were  performed.  The abdominal  withdrawal  reflex  (AWR)  scores  were  recorded.  The  expression  of  prepro-orexin  and  orexin receptor  2  (OX2R)  in  the  colon  and  cerebral  cortex  was  examined  using  in  situ  hybridization  (ISH)  and immunohistochemical detection. Results: Compared with the normal group, the IBS group had higher AWR scores (P<0.01) while the scores were lower in the WM group than IBS group (P<0.05). ISH assays showed that the expression of prepro-orexin and OX2R mRNA in the cerebral cortex and colon was reduced in the IBS group compared to the normal group (P<0.01), and was increased in the WM group compared to the IBS group (P<0.01). The immunohistochemical results were consistent with the ISH. Conclusion: The effect of improving visceral hypersensitivity by warming moxibustion may be associated with the up-regulation of abnormally reduced expression of prepro-orexin and OX2R in the colon and cerebral cortex. 

Key words:  Acupuncture and moxibustion, Irritable bowel syndrome, warming moxibustion, prepro-orexin, OX2R