环孢霉素A阻断刀豆蛋白A肝损害肝细胞表达一氧化氮合酶的研究

THE INHIBITORY EFFECT OF CYCLOSPORIN A ON THE EXPRESSION OF NITRIC OXIDE SYNTHASE FOLLOWING CONCANAVALIN A INDUCED LIVER INJURY IN MICE

以刀豆蛋白A(ConA)诱发的小鼠肝损害为实验模型 ,观察环孢霉素A(CsA)对肝细胞表达一氧化氮合酶 (NOS)的影响。结果显示 ,对照组小鼠肝细胞未见NOS表达 ;ConA诱发肝损害后 ,肝细胞大量表达NOS,且越靠近中央静脉的肝细胞表达越多 ;用CsA预先抑制T细胞活化 ,则肝细胞表达NOS亦同时被阻断。上述实验结果提示 ,肝细胞表达NOS可能是对缺血缺氧的自身保护性反应 ,CsA通过抑制T细胞活化而阻断肝细胞表达NOS。

This study was to study the effect of cyclosporine A (CsA) on the expression of nitric oxide synthase (NOS) in liver cells in T cell dependent liver injury induced by concanavalin A (ConA) in mice. The results showed that there was no NOS expression in the normal murine hepatocytes. Affer ConA challenge, the expression of NOS in hepatocytes increased markedly.Moreover, the hepatocytes closer to the central vein showed stronger expression.After pretreatment of CsA, activation of T lymphocytes was inhibited and NOS expression in the hepatocytes was almost completely inhibited too.The above results suggest that an upregulation of NOS expression might be a protective response to insufficient supply of blood and oxygen as a result of ConA induced liver injury, and inhibition of the NOS expression by CsA might be associated with inactivation of T lymphocyte.