A study of the modified type II spectral change produced by the interaction of agroclavine with cytochrome P-450

Previous work in this laboratory has demonstrated that agroclavine is metabolized by liver microsomes and that cytochrome P-₄₅₀ is involved as the terminal oxidase in the reaction. Addition of agroclavine to suspensions of liver microsomes in the same concentration as used in the metabolic studies produced a modified Type II spectral change with peak near 420 nm and trough near 390 nm. Using modifiers such as hexobarbital, this spectrum has now been shown to contain a Type 1 component. Furthermore, when sufficiently low concentrations of agroclavine were added to rat liver microsomes, a Type I spectral change appeared, which gradually turned into the modified Type II variety upon increase in agroclavine concentration.