丹酚酸A对大鼠脑缺血再灌注损伤后胞浆型磷脂酶A2表达的影响及机制研究

摘要

Objective To study the effect of salvianolic acid A on expression of cytosolic phospholipase A2 (cPLA2) in rats following cerebral IR injury and its mechanism.Methods Sixty-five SD rats were randomly divided into control group,model group,salvianolic acid A treatment group and LY294002+salvianolic acid A treatment group (20 in each group).Brain tissue samples were taken from ischemic stroke rats at 0,8,24 and 48 h after reperfusion.Apoptosis was assayed by TUNEL,expressions of cPLA2,Akt and phosphorylated Akt were detected by Western blot withimmunohisto chemical staining.Results The number of TUNEL-positive cells was greater and the expression level of cPLA2 was significantly higher while the expression level of phosphorylated Akt was significantly lower in model group and LY294002-±-salvianolic acid A treatment group than in control group at 0,8,24,48 h after reperfusion (P＜0.05).The expression level of phosphorylated Akt was significantly higher while the number of TUNEL-positive cells was significantly smaller and the expression level of cPLA2 was significantly lower in salvianolic acid A treatment group than in model group at 0,8,24,48 h after reperfusion (P＜0.05).Conclusion Salvianolic acid A inhibits the expression of cPLA2 and reduces the apoptosis through the Akt pathway,thus playing a role in protecting cells in rats following IR injury.%目的 探讨丹酚酸A对大鼠脑缺血再灌注损伤后胞浆型磷脂酶A2(cytosolic phospholipase A2,cPLA2)表达的影响及其机制.方法 将SD大鼠65只,随机分为对照组,模型组、丹酚酸A组和联合组(LY294002+丹酚酸A).分别于再灌注后0、8、24、48 h取梗死脑组织,用TUNEL检测脑细胞凋亡,免疫组织化学检测cPLA2表达,Western blot检测蛋白激酶B(Akt)、磷酸化Akt在脑组织表达水平.结果 模型组和联合组0、8、24、48 h海马CAl区TUNEL阳性细胞和cPLA2表达较对照组明显增高,脑组织磷酸化Akt表达较对照组明显降低(P＜0.05).丹酚酸A组0、8、24、48 h脑组织磷酸化Akt表达较模型组明显增高,TUNEL阳性细胞和cPLA2表达较模型组明显降低[(10.1±5.3)个/mm2 vs (12.8±4.7)个/mm2、(14.6±6.2)个/mm2 vs (30.1±7.5)个/mm2、(19.7±6.5)个/mm2 vs (73.8±11.4)个/mm2、(22.8±9.6)个/mm2 vs (94.6±15.2)个/mm2,(13.6±3.1)个/mm2 vs (41.3±3.6)个/mm2、(14.8±4.7)个/mm2 vs (62.5±6.9)个/mm2、(16.6±7.1)个/mm2 vs (72.3±9.6)个/mm2、(17.0±5.3)个/mm2 vs (83.2±11.7)个/mm2,P＜0.05].结论 丹酚酸A通过Akt信号通路,降低脑缺血再灌注后脑组织中cPLA2表达,减少脑细胞凋亡,发挥细胞保护作用.