GPR30在17β雌二醇抑制氯胺酮致幼鼠海马神经细胞凋亡中的作用:与p-ERK1/2表达的关系

Role of GPR30 in 17βestradiol-induced inhibition of ketamine-caused neuroapoptosis in hippocampus of newborn rats:the relationship with p-ERK1/2

目的评价G蛋白偶联受体30(GPR30)在17β雌二醇抑制氯胺酮致幼鼠海马神经细胞凋亡中的作用及其与磷酸化细胞外信号调节激酶1/2(p-ERK1/2)表达的关系。方法清洁级健康雄性SD大鼠24只,7日龄,体重11~18 g,采用随机数字表法分为4组(n=6):对照组(C组)、氯胺酮组(K组)、17β雌二醇+氯胺酮组(EK组)和GPR30抑制剂G15+17β雌二醇+氯胺酮组(G15EK组)。K组腹腔注射氯胺酮75 mg/kg(生理盐水稀释至0.1 ml),EK组皮下注射17β雌二醇600μg/kg和腹腔注射氯胺酮75 mg/kg,G15EK组皮下注射GPR30抑制剂G15300μg/kg和17β雌二醇600μg/kg,腹腔注射氯胺酮75 mg/kg,C组腹腔注射生理盐水0.1 ml。每隔24 h注射1次,连续注射3 d。于末次注射后24 h时处死大鼠取海马,采用Western blot法检测cleaved caspase-3、ERK1/2和p-ERK1/2表达。结果4组海马ERK1/2表达水平比较差异无统计学意义(P>0.05)。与C组比较,K组和G15EK组海马cleaved caspase-3表达上调,p-ERK1/2表达下调(P<0.05);与K组比较,EK组cleaved caspase-3表达下调,p-ERK1/2表达上调(P<0.05);与EK组比较,G15EK组海马cleaved caspase-3表达上调,p-ERK1/2表达下调(P<0.05)。结论GPR30参与了17β雌二醇抑制氯胺酮致幼鼠海马神经细胞凋亡的过程,与上调p-ERKl/2表达有关。

Objective To evaluate the role of G protein-coupled receptor 30(GPR30)in 17βestradiol-induced inhibition of ketamine-caused neuroapoptosis in the hippocampus of newborn rats and the relationship with phosphorylated extracellular signal-regulated kinase 1/2(p-ERKl/2).Methods Twenty-four clean-grade healthy male Sprague-Dawley rats,aged 7 days,weighing 11-18 g,were divided into 4 groups(n=6 each)using a random number table method:control group(group C),ketamine group(group K),17βestradiol plus ketamine group(group EK),and GPR30 inhibitor G15 plus 17βestradiol plus ketamine group(group G15EK).Ketamine 75 mg/kg(diluted to 0.1 ml in normal saline)was intraperitoneally injected every 24 h for 3 consecutive days in group K.In group EK,17βestradiol 600μg/kg was subcutaneously injected and ketamine 75 mg/kg was intraperitoneally injected every 24 h for 3 consecutive days.G15300μg/kg and 17βestradiol 600μg/kg were subcutaneously injected and ketamine 75 mg/kg was intraperitoneally injected every 24 h for 3 consecutive days in group G15EK.The equal volume of normal saline 0.1 ml was intraperitoneally injected instead in group C.The animals were sacrificed at 24 h after the last injection for determination of the expression of cleaved caspase-3,ERK1/2 and phosphorylated ERK1/2(p-ERK1/2)(by Western blot).Results There was no significant difference in the expression of ERK1/2 in hippocampus among the four groups(P>0.05).Compared with group C,the expression of cleaved caspase-3 was significantly up-regulated,and the expression of p-ERK1/2 was down-regulated in K and G15EK groups(P<0.05).Compared with group K,the expression of cleaved caspase-3 was significantly down-regulated,and the expression of p-ERK1/2 was up-regulated in group EK(P<0.05).Compared with group EK,the expression of cleaved caspase-3 was significantly up-regulated,and the expression of p-ERK 1/2 was down-regulated in group G15EK(P<0.05).Conclusion GPR30 is involved in 17βestradiol-induced inhibition of ketamine-caused neuroapoptosis in the hippocampus of newborn rats,which is related to up-regulating the expression of p-ERKl/2.