肺保存液复合硫化氢对大鼠供体肺冷缺血期肺组织内质网应激的影响

摘要

目的 探讨供体肺保存液中加入外源性硫化氢(H2S)对大鼠供体肺冷缺血期肺组织内质网应激的影响.方法 将28只健康雄性SD大鼠分为对照组、LPD组和硫氢化钠(NaHS)组.NaHS组即在低钾右旋糖酐液(LPD液)中加入NaHS,并根据不同剂量(20 mmol/L和40 mmol/L)进一步分为NaHS20组和NaHS40组.对照组大鼠处死后用LPD液行肺灌注后即取标本保存待检,后3组大鼠放血处死后分别用相应的液体行肺灌注后行低温保存肺脏2h.测定肺组织匀浆中H2S含量、H2S生成酶胱硫醚-γ-裂解酶(CSE),观察肺组织中细胞凋亡的情况.采用免疫印迹(Westernblot)法测定肺组织中GRP78及PERK蛋白表达.结果 与对照组相比,LPD组肺组织中H2S含量及CSE活性无显著变化(P＞0.05),NaHS组H2S含量及CSE活性显著升高(P＜ 0.05),不同剂量NaHS组间比较,差异无统计学意义(P＞0.05).与对照组相比,LPD组及NaHS组凋亡细胞百分比显著升高(P＜0.05);与LPD组相比,NaHS组凋亡细胞百分比显著降低(P＜0.05);NaHS组间相比,差异无统计学意义(P＞0.05).与对照组相比,LPD组及NaHS组肺组织GRP78及PERK蛋白表达显著增加(均P＜ 0.05);与LPD组相比,NaHS组GRP78及PERK蛋白表达显著下降(P＜0.05),NaHS组间差异无统计学意义(P＞0.05).结论 肺保存液中复合H2S可显著增加肺组织中H2S含量及CSE活性,降低内质网应激相关蛋白GRP78及PERK蛋白表达,减少细胞凋亡.%Objective To investigate the effects of preservation solution supplemented with exogenous hydrogen sulfide (H2S) on endoplasmic reticulum stress (ERS) in donor lung tissue during cold ischemia in rats.Methods 28 healthy SD rats were divided into a control group,an LPD group,and a NaHS group.The NaHS group added NaHS as H2S donor to the low potassium dextran solution (LDP solution) and was further divided,into a NaHS20 group and a NaHS40 group according to different NaHS doses——20 mmol/L and 40 mmol/L.All the rats were killed by exsanguination.The lungs in the control group were immediately preserved at-70℃ after perfusion with LPD solution.In the other three groups,the lungs were perfused with corresponding solution and then were saved at 4℃ for 2 h.The H2S concentration and cystathionine-γ-lyase (CSE) of H2S production in lung tissue homogenization were observed.The severity of apoptosis in lung tissue was observed.The expressions of GRP78 and PERK in lung tissue were determined by westemblot.Results Compared with those in the control group,the H2S concentration and CSE activity were not significantly different from those in the LPD group (both P ＞ 0.05),and significantly increased in the NaHS group (both P ＜ 0.05).However,there were no statistical differences in the H2S concentration and CSE activity between the NaHS groups (both P ＞ 0.05).Compared with that in the control group,the percentage of apoptosis increased significantly in the LPD group and the NaHS group (both P ＜ 0.05).Compared with that in the LPD group,the percentage of apoptosis decreased significantly in the NaHS groups (P ＜ 0.05),but there was no statistical difference in the percentage of apoptosis between the NaHS groups (P ＞ 0.05).Compared with those in the control group,the expressions of GRP78 and PERK were significantly higher in LPD group and NaHS group (all P ＜ 0.05).Compared with those in the LPD group,the expressions of GRP78 and PERK significantly decreased in the NaHS group (both P ＜ 0.05).There were no statistical differences in the expressions of GRP78 and PERK between the NaHS groups (P ＜ 0.05).Conclusions Lung preservation solution supplemented with H2S significantly increases H2S concentration and CSE activity in lung tissue,reduces ERS-related protein expressions of GRP78 and PERK,and inhibits apoptosis in lung tissue.