Studies on the mechanism of action of isopropyl N-phenyl carbamate

The binding of [ 14C]isopropyl N-phenyl carbamate (IPC) to microtubular protein isolated from chick brains, and the effect of isopropyl N-phenyl carbamate (IPC) on the in vitro reassembly of microtubules was investigated. While [ 14C]colchicine binds to microtubular protein, [ 14C]IPC does not. Concentrations from 1 × 10 −4 M to 1 × 10 −3 M IPC do not prevent in vitro repolymerization of microtubular protein. IPC (1 × 10 −4 M) does not affect the rate of reassembly of microtubules. We conclude that IPC does not exert its effect through an interaction with microtubular protein; we suggest that IPC probably interacts with microtubule organizing centers.