FLASH PHOTOLYSIS OF MICROSOMAL P450

该仪器用于测量一氧化碳(CO)的动力学。 大鼠肝微粒体中细胞色素P450的结合 各种药物和致癌物质。当一氧化碳直接加入大鼠肝脏时 微粒体，450 nm处的吸光度变化太快而不能跟随 在标准的分光光度计上。为了观察到这一快速 采用连续染料-激光闪光光解装置， 用于监测吸光度变化的动力学。 重组数据一般符合三指数动力学模型。 然而，每个指数都包含了几种P450形式的贡献。 为了确定单个P450的动力学参数，a 采用差分动力学方法，利用两种方法之间的差异 在没有和存在特定P450的情况下的动力学分布 效应器。这一新方法成功地获得了动力学参数 微粒体P450。

This instrument is used to measure the kinetics of carbon monoxide (CO) binding to cytochrome P450 in liver microsomes from rats treated with various drugs and carcinogens. When CO is added directly to rat liver microsomes, the absorbance change at 450 nm occurs too rapidly to follow on a standard spectrophotometer. In order to observe this rapid reaction, a continuous dye-laser flash photolysis apparatus was constructed to monitor the kinetics of the absorbance change. Recombinant data generally were fit to a three-exponential kinetic model. However, each exponent included the contribution of several P450 forms. In order to determine the kinetic parameter for individual P450s, a difference kinetic method was used that employs the difference between the kinetic profiles in the absence and presence of a specific P450 effector. This new approach successfully yielded kinetic parameters for microsomal P450.