In vitro covalent binding of acrylonitrile to rat liver proteins.

The irreversible protein binding of [3-14C]acrylonitrile (ACN) was evaluated in the presence of microsomes, cytosolic and post-mitochondrial fractions of rat liver. Spontaneous binding was measured after incubation of ACN in the presence of the various liver fractions at 4 degrees C and 37 degrees C respectively and in a comparative study performed at 37 degrees C in the presence of S9 or bovine serum albumin (BSA). The effect of various inducers and inhibitors was investigated. A spontaneous binding resulting from a direct alkylation by ACN seemed to play an important role; however, binding resulting from the microsomal activation of ACN into reactive intermediate(s) was also detected.