垂体腺苷酸环化酶激活肽对大鼠局灶性脑缺血/再灌注损伤脑保护作用的研究

目的观察垂体腺苷酸环化酶激活肽(PACAP)对大鼠局灶性脑缺血/再灌注损伤的脑保护作用。方法采用线栓法制备大鼠局灶性脑缺血/再灌注损伤(MCAO)模型,缺血前经侧脑室分别给予不同剂量的PACAP,脑缺血2 h/再灌注24 h,测定脑含水量、脑组织超氧化物歧化酶(SOD)活性和丙二醛(MDA)、一氧化氮(NO)含量。结果与NS组相比,PACAP各组脑含水量、MDA及NO含量均明显降低,SOD活性有不同程度的提高。结论PACAP对大鼠局灶性脑缺血/再灌注损伤有明显的脑保护作用,中、高剂量组效果优于低剂量组,其机制可能与减轻脑水肿、清除自由基、抗脂质过氧化有关。

Protective effect of pituitary adenylate cyclase activating polypeptide on focal cerebral ischemia reperfusion injury in rats

Aim To investigate the protective effect of pituitary adenylate cyclase activating polypeptide(PACAP)on focal cerebral ischemia reperfusion injury in rats.Methods The models of focal cerebral ischemia reperfusion in rats were established with suture-occluded method to simulate the middle cerebral artery ischemia reperfusion injury in clinic.The treatment groups were given three different dose PACAP(PACAP 10-11 mol,PACAP 10-10 mol and PACAP 10-9 mol) in 15 minutes before cerebral ischemia.PACAPs were infused into lateral cerebral ventricle by microinjector.The water content of brain,the activity of superoxide dismutase(SOD),the content of malondialdehyde(MDA) and the content of nitrogen monoxidum(NO) of the brain tissue were determined.Results Compared with NS group,the water content of brain and the concentration of MDA and NO were obviously lower in each PACAP treatment group,while the activity of SOD was elevated to different degrees.Conclusion PACAP has an obvious protective effect on ischemia-reperfusion injury of focal brain tissue in rats,in which edema-alleviating,free radicals-scavenging and lipid peroxidation-attenuating could be involved.The protective effect seems to be more clear in middle-and high-dose group than in low-dose group.