Study on the influence of acupoints selection on ghrelin and GHSR expression in gastric fundus tissue of DGP rats

Abstract

Objective: To explore the acupoint selection compatibility according to different departments and to study the influence on ghrelin and GHSR expression in the gastric fundus in rats with Diabetic Gastroparesis (DGP). Methods: Sixty male SPF SD rats were given adaptive feeding for one week and were randomly divided into a blank control group, a model group, the Zusanli and Zhongwan (ZZ) group, the Zusanli and Neiguan group (ZN), as well as the Zusanli and non-meridian acupoint (ZNA) group, with 12 rats in each group. Except for the blank group, the other 48 rats were used to establish a DGP model by using streptozotocin. Acupuncture therapy was performed from the end of the tenth week for an additional four weeks. Then the rats were sacrificed and the serum and gastric fundus tissues were collected. ELISA assay was used to detect the ghrelin content in the serum. The expression of ghrelin positive cells in the gastric fundus tissue was detected by immunohistochemistry. The expression of ghrelin and GHSR mRNA in the gastric fundus tissue was detected by real-time PCR. Results: Compared with the blank group, the food intake and the expression of ghrelin and GHSR mRNA in the gastric fundus tissue in the model group were significantly increased, while the small intestinal propulsion rate, the ghrelin content in the serum and the gray value of the gastric fundus were significantly decreased (P<0.05). Compared with the model group, the expression of ghrelin and GHSR mRNA in the gastric fundus tissue, the small intestinal propulsion rate, the ghrelin content in the serum and the gray value of the gastric fundus were significantly increased (P<0.05). Compared with the ZZ group, the food intake were significantly increased in the ZN and the ZNA groups (P<0.05), and the expression of ghrelin and GHSR mRNA in the gastric fundus tissue of rats were significantly increased (P<0.05) but the ghrelin content in the serum in ZN group was significantly decreased (P<0.05). Conclusions: The improvement of gastrointestinal motility in DGP by acupuncture therapy was associated with the ghrelin content in the serum and GHSR expression in the gastric fundus. The treatment effect of local acupoints compatibility was better than that of the distal acupoints compatibility, and the acupoint selection according to department was one of the main influencing factors of acupoints compatibility.