[Effects of Different Acupuncture and Moxibustion Methods on Plasma NO, NOS and VIP Contents and the Expression of Colonic VIP Protein in Functional Constipation Rats].

Objective: To compare the effects of filiform needling, electroacupuncture, and moxibustion on functional constipation in rats, and to explore the possible mechanism of these three different methods.

Methods: Male SD rats were randomly divided into blank control group (=8), model group (=11), medication group (=8), filiform needling group (=11), electroacupuncture group (=11), and moxibustion group (=11). Functional constipation model was established by intragastric administration with the suspension of loperamide hydrochloride, daily for six days in a week. One hour after each gavage, the medication group was treated with cisapride suspension, while the other three groups were treated with filiform needling, electroacupuncture, and moxibustion, respectively, at "Tianshu"(ST 25), "Shangjuxu" (ST 37) acupoints. The first defecation time was recorded. NO, NOS and VIP (vasoactive intestinal peptide) levels in plasma were detected by ELISA. Immuohistochemical and Western blot methods were applied to test VIP expression in the colonic tissue.

Results: Compared with the blank control group, the first defecation time was prolonged, and the NO, NOS and VIP contents in plasma were increased in the model group (<0.05, <0.01), accompanied with increased score of VIP in the smooth muscle of colonic wall(<0.05)and elevated VIP expression in colonic tissue(<0.01). Compared with the model group, the first defecation time was shortened in the medication, filiform needling, electroacupuncture, and moxibustion groups(<0.05), while decreased NO, NOS and VIP contents in plasma (<0.01,<0.05), decreased score of VIP in the smooth muscle of colonic wall(<0.05), and lower expression level of VIP in colonic tissue(<0.01)were observed in the four treatment groups. In contrast, the plasma VIP content in the electroacupuncture group was lower than that in the medication group (<0.01), while colonic VIP expression decreased in the moxibustion group(<0.01). The NO, NOS and VIP contents in plasma and score of VIP in the smooth muscle of colonic wall in the electroacupuncture group were lower than those in the filiform needling group and the moxibustion group(<0.01, <0.05), but the colonic VIP expression in the moxibustion group was lower than that in the filiform needling group(<0.05)and electroacupuncture group(<0.01).

Conclusions: All the three different kinds of acupuncture and moxibustion methods have positively regulatory effect on functional constipation; electroacupuncture is the best for the regulation of plasma NO, NOS and VIP contents, while moxibustion is the best for the regulation of VIP expression in colonic tissue.