代谢
我们最近发现,当给予大鼠吸入性麻醉剂氟烷时,一种58 kDa的内质网蛋白会被氟烷代谢物三氟乙酰氯共价三氟乙酰化。尽管这个58 kDa蛋白与据报道对应于磷脂酰肌醇特异性磷脂酶C-α的cDNA推导的氨基酸序列有99%的同一性,但它并没有磷脂酰肌醇特异性磷脂酶C的活性。因此得出结论,报道的磷脂酰肌醇特异性磷脂酶C-α的cDNA实际上编码了一个未知功能的58 kDa内质网蛋白。其他研究者也得出了相同的结论,并显示这个58 kDa蛋白具有蛋白质二硫键异构酶和蛋白酶活性。我们现在报告,患有氟烷肝炎的患者的血清中有抗体与纯化的三氟乙酰化和天然大鼠肝脏58 kDa蛋白反应。这些结果表明,当患者暴露于氟烷时,会形成一种与大鼠肝脏三氟乙酰化-58 kDa蛋白同源的人类肝脏蛋白。在某些患者中,这种蛋白可能变得具有免疫原性,并导致形成特异性抗体和/或特异性T细胞,这些抗体和T细胞可能与三氟乙酰化和天然58 kDa蛋白反应,并最终至少部分地导致氟烷引起的肝炎。
We recently showed that when rats were administered the inhalation anesthetic halothane, a 58 kDa liver endoplasmic reticulum protein became covalently trifluoroacetylated by the trifluoroacetyl chloride metabolite of halothane. Although the 58 kDa protein showed 99% identity to that of the deduced amino acid sequence of a cDNA reported to correspond to phosphatidylinositol-specific phospholipase C-alpha, it did not have phosphatidylinositol-specific phospholipase C activity. It was concluded that the reported cDNA of phosphatidylinositol-specific phospholipase C-alpha actually encoded for the 58 kDa endoplasmic reticulum protein of unknown function. Other researchers have come to the same conclusion and have shown that the 58 kDa protein has protein disulfide-isomerase and protease activities. We now report that patients with halothane hepatitis have serum antibodies that react with both purified trifluoroacetylated and native rat liver 58 kDa proteins. These results suggest that when patients are exposed to halothane a human liver orthologue of the rat liver trifluoroacetylated-58 kDa protein is formed. In certain patients, this protein may become immunogenic and lead to the formation of specific antibodies and or specific T-cells, which may react with both trifluoroacetylated and native 58 kDa proteins, and ultimately be responsible, at least in part, for the hepatitis caused by halothane.
来源:Hazardous Substances Data Bank (HSDB)