[Study of populations of nuclear RNA of rat liver cells after short-term exposure to a carcinogen].

RNA-DNA hybridization in a solution with DNA excess was employed. Rat's livers were given one injection of 4-dimethylaminoazobenzene, and, when compared 24 hours afterwards with livers from normal untreated rats, demonstrated an altered transcription. The hybridization capacity of the nuclear RNA isolated from carcinogen-treated livers is lower than that of the control RNA.