Inhibition of galactosamine cytotoxicity in an in vivo/in vitro hepatocellular toxicity model.
Inhibition of galactosamine cytotoxicity in an in vivo/in vitro hepatocellular toxicity model.
复制标题
在体内/体外肝细胞毒性模型中抑制半乳糖胺细胞毒性。
DOI：
10.1016/0041-008x(87)90047-0
复制
发表时间：
1987
影响因子：
3.8
通讯作者：
White,C
中科院分区：
文献类型：
--
作者：
MacDonald,JR;Thayer,KJ;White,C
采用半乳糖胺肝毒性的体内/体外联合模型，验证半乳糖胺对半乳糖胺所致肝损伤的保护作用是否与半乳糖胺对毒物激发的肝细胞的直接作用有关。在该模型中，雄性SD大鼠在门静脉插管前1小时通过腹腔注射400 mg/kg氨基半乳糖进行肝细胞分离。在单层培养中建立分离的细胞，然后在接下来的24-48小时内表达氨基半乳糖引起的细胞损伤。与氨基半乳糖诱导的体内肝细胞损伤的生化基础一致，体外尿苷治疗可以在体内注射氨基半乳糖后3小时内预防细胞毒性，但在12小时后加入尿苷则不能。相比之下，即使在体内毒物挑战后12小时加入培养物中，半胱胺也显示出细胞保护作用。体外染毒后半胱胺的细胞保护作用呈浓度依赖性，对肝细胞非蛋白巯基含量无明显影响。在这种体内/体外毒性模型中，尿苷和半胱胺对中毒后细胞的保护作用与这些药物对氨基半乳糖诱导的坏死的体内保护完全一致。该模型消除了半胱胺的肝保护作用的潜在的“肝外”机制，并显示了对氨基半乳糖挑战的肝细胞的直接细胞保护作用。
A combined in vivo/in vitro model of galactosamine hepatotoxicity was employed to test whether previously reported cytoprotective actions of cystamine administration on galactosamine-induced hepatic injury in vivo could be attributed to a direct action of cystamine on toxicant-challenged hepatocytes. In this model, male Sprague-Dawley rats received a 400 mg/kg galactosamine challenge via intraperitoneal injection 1 hr prior to portal vein cannulation for hepatocyte isolation. Isolated cells are established in monolayer culture and galactosamine-induced cellular injury is then expressed over the ensuing 24–48 hr in culture. Consistent with the biochemical basis of galactosamine-induced hepatocellular injury in vivo, cytotoxicity could be prevented by in vitro uridine treatments within 3 hr of the in vivo galactosamine challenge, but not when added 12 hr later. Cystamine, in contrast, exhibited a cytoprotective effect even when added to cultures 12 hr after the in vivo toxicant challenge. Post-toxicant cytoprotection by cystamine in vitro was concentration dependent and did not produce an alteration of hepatocyte nonprotein sulfhydryl content. Post-toxicant cytoprotection by uridine and cystamine in this in vivo/in vitro model of toxicity were fully consistent with in vivo protection from galactosamine-induced necrosis by these agents. This model eliminates potential “extrahepatic” mechanisms for cystamine's hepatoprotective effect and demonstrates a direct cytoprotective action on galactosamine-challenged hepatocytes.