胃溃疡小鼠体表穴位敏化与垂体腺苷酸环化酶激活肽作用关系研究OA北大核心CSTPCD

Objective To explore the expression,effect and mechanism of pituitary adenylate cyclase activating peptide(PACAP)in the process of acupoint sensitization in gastric ulcer mice from the perspective of molecular biology.Methods Fifty-eight male C57BU6J mice were randomly divided into the control group(n=28)and the model group(n=30).In the model group,60％glacial acetic acid was injected into the gastric wall near the submucosa at the paragastric curve near the pylorus to construct a gastric ulcer mouse model,and the control group was injected with the same dose of saline.After injecting Evans blue(EB)staining solution into the tail vein of mice,the number,distributions and regularity of exudation points on the body surface were observed on the 6th day of modeling.Mechanical and thermal pain thresholds were measured to evaluate the changes in pain sensitivity of mice.Hematoxylin-eosin(HE)staining was used to observe the gastric histopathological changes in mice.Western Blot and immunofluorescence staining were used to observe the expression of PACAP in dorsal root ganglion(DRG)neurons,the skin of the surface innervation area and the spinal dorsal horn in the T9-T11 segments of the mouse spinal cord after acupoint sensitization.Results Compared with the control group,the gastric tissue of the model group was significantly damaged,eosinophils increased,and inflammatory cells infiltrated.The number of EB exudation points in the model group was significantly higher.These points were mainly distributed on the body surface of the spinal cord in segments T6-L1,and the most concentrated in the T9-T11 region.Furthermore,the pain threshold of the model group mice was remarkably decreased(P＜0.01).After acupoint sensitization occurs,the levels of PACAP expression in the dorsal skin,spinal dorsal horn,and DRG neurons of the T9-T11 segments of the spinal cord in the model group were enhanced,respectively(P＜0.01).Conclusions The expression of PACAP on DRG neurons of the T9-T11 segments of the spinal cord,which are responsible for transmitting visceral pain information,is improved in gastric ulcer mice.Then,it promotes the local neurogenic inflammatory reactions on the body surface from the central and peripheral aspects,by increasing the expression of PACAP in the superficial dorsal horn of the spinal cord and the innervation area of the body surface.These effects might explain the mechanism of acupoint sensitization.