HO-1在七氟烷预处理抑制大鼠氧糖剥夺海马神经元凋亡中的作用

目的 探讨血红素氧合酶-1(HO-1)在七氟烷预处理抑制大鼠氧糖剥夺海马神经元凋亡中的作用.方法 出生48 h内的Wistar大鼠,体外培养海马神经元,随机分为6组,每组108孔,正常对照组(C组):不做任何处理;2%七氟烷预处理组(S1组):2%七氟烷预处理60 min后正常培养24 h;OGD组:缺糖缺氧45 min后复糖复氧,再正常培养24 h以制备氧糖剥夺模型;2%七氟烷预处理+OGD 组(S1+OGD组)和4%七氟烷预处理+OGD组(S2+OGD组):分别经2%、4%七氟烷预处理后制备氧糖剥夺模型;4%七氟烷预处理+ZnPPⅨ+OGD(Z组):4%七氟烷预处理同时在培养液中加入ZnPPⅨ(终浓度10 μmol/L),其余处理同S2+OGD组.正常培养24 h时检测神经元存活率、凋亡率和HO-1蛋白及其mRNA的表达水平.结果 与C组比较,OGD组、S1+OGD组、S2+OGD组和Z组海马神经元存活率降低,凋亡率升高,海马神经元HO-1 mRNA及其蛋白表达上调,S1组海马神经元HO-1 mRNA 及其蛋白表达上调(P<0.01),神经元存活率、凋亡率差异无统计学意义(P>0.05);与OGD组比较,S1+OGD组、S2+OGD组海马神经元存活率升高,凋亡率降低,海马神经元HO-1 mRNA及其蛋白表达上调,Z组上述指标差异无统计学意义(P>0.05);与S1+OGD组比较,S2+OGD组海马神经元存活率升高,凋亡率降低,海马神经元HO-1 mRNA及其蛋白表达上调(P<0.01);与S2+OGD组比较,Z组海马神经元存活率降低,凋亡率升高,海马神经元HO-1 mRNA及其蛋白表达下调(P<0.01).结论 HO-1可能参与了七氟烷预处理抑制大鼠氧糖剥夺海马神经元凋亡的机制.

Role of HO-1 in inhibition of oxygen-glucose deprivation-induced apoptosis in rat hippocampal neurons by sevoflurane preconditioning

Objective To investigate the role of HO-1 in inhibition of oxygen-glucose deprivation (OGD)-induced apoptosis in rat hippocampal neurons by sevoflurane preconditioning.Methods Hippoeanlpal neurons of newborn Wistar rats (<48 h) were cultured in vitro.Tne neurons were randomly divided into 6 groups with 108 wells in each group:control group(group C),2% sevoflurane preconditioning group (group S1),OGD group,S1 +OGD group,4% sevoflurane preconditioning+OGD group (group S2+OGD),and 4% sevoflurane preconditioning+ZnPPⅨ+OGD group(group Z).Group C received no treatment.The neurons were cultured for 24 h after 2% sevoflurane preconditioning in group S1.For OGD experiments,the neurons were placed in deoxygenated glucose-free medium and sealed under 95% N2-5% CO2 in an anaerobic chamber equilibrated to 37℃ and 100%humidity for 45 min.then OGD was terminated by replacement of the stored medium and returning the cultures to a standard incubator maintained at 37℃ in 5% C02 and the neurons were cultured for 24 h as described by Ray et al. The OGD model was established after 2% and 4% sevoflurane preconditioning in group S1 + OGD and S2 + OGD respectively. In group Z, when the neurons were preconditioned with 4% sevoflurane, ZnPPⅨ was added to the culture medium at the same time, and the other procedures were the same as those in group S2 + OGD. The neuron viability, apoptesis rate, and expression of HO-I protein and mRNA were detected at 24 h of culture. Results Compared with group C, neuron viability was significantly decreased,apoptosis rate was significantly increased, and expression of HO-1 protein and mRNA was up-regulated in group OGD, S1 + OGD, S2 + OGD and Z, expression of HO-1 protein and mRNA was up-regulated in group S1 ( P < 0.01 ), but no significant change was found in neuron viability and apoptosis rate in group S1 ( P > 0.05). Compared with group OGD, neuron viability was significantly increased, apoptosis rate was significantly decreased, and expression of HO-1 protein and mRNA was up-regulated in group S1 + OGD and S2 + OGD ( P < 0.01), but no significant change was found in the indexes mentioned above in group Z ( P > 0.05 ). Neuron viability was significantly higher, apoptosis rate lower and expression of HO-1 protein and mRNA higher in group S2 + OGD than in group S1 + OGD ( P < 0.01). Neuron viability was significantly lower, apoptosis rate higher and expression of HO-1 protein and mRNA lower in group Z than in group S2+OGD(P<0.01).Conclusion HO-1 is involved in the inhibition of OGD-indueed apoptosis in rat hippocampal neurons by sevoflurane preconditioning.