RESUMEN
Objective To study the effects of electroacupuncture(EA)on gastrointestinal motility and nitric oxide synthase(NOS)positive nerves in myenteric plexus in acute exhaustive exercise rats. Methods A total of 54 male Sprague-Dawley rats were randomly divided into an acute exhaustive exercise(AEE)group,an AEE plus EA group and a control(C)group.The gastric empty rate and intestinal motility rate were measured,and histological changes of NOS-positive nerves in ileum myenteric plexus were observed with enzymatic histochemical method and image analysis technique. Results In the rats of AEE group,the gastric empty rate and intestinal motility rate were delayed but the numbers of NOS-positive neurons and expression levels of NOS in the ileum myenteric plexus significantly increased comparing with those of the C group(P＜0.01).Compared with AEE group,the gastric empty rate and intestinal motility rate were significantly increased but the number of NOS-positive neurons and expression level of NOS in the ileum myenteric plexus significantly decreased in AEE plus EA group(P＜0.01). Conclusion The findings of this study suggest that increase of NOS-positive neurons and expression levels of NOS in the myenteric plexus is one of the mechanisms of slowing down of gastrointestinal movement after acute exhaustive exercise.Electroacupuncture at Zusanli acupoint may decrease the number of NOS-positive neurons and expression levels of NOS in the myenteric plexus,and improve gastrointestinal movement in acute exhaustive exercise rats.