Inhibition of metabolic cooperation by the anticonvulsants, diphenylhydantoin and phenobarbital.

High densities of 6-thioguanine-sensitive Chinese hamster V79 cells reduce the recovery of co-cultured 6-thioguanine-resistant cells through a form of intercellular communication (metabolic cooperation). Diphenylhydantoin and phenobarbital, suspected human and animal teratogens and tumor promoters, were able to inhibit intercellular communication at noncytotoxic doses. A potentiation was observed when a mixture of the two chemicals was used.