Studies of the tumorigenic potential of 4‐substituted phenylhydrazines by the subcutaneous route

Abstract

4‐Methylphenylhydrazine hydrochloride (4‐MPH) was administered to randomly bred Swiss mice as 26 weekly sc infections of 140 μg per gram of body weight and N'‐acetyl‐4‐(hydroxymethyl)phenylhydrazine (AMPH) as 26 weekly sc injections of 500 μg/g. As o solvent control, physiological saline was also given as 26 weekly sc injections of 0.01 ml/g. The 4‐MPH treatment induced a significant incidence (24%) of fibrosarcomas in males. In the 4‐MPH‐treated females and some AMPH‐treated male mice, a few soft‐tissue tumors were observed; however, their appearance could not be related to treatment.

4‐MPH is formed under special experimental conditions from 4‐hydroxymethylphenylhydrazine, which is an in vitro breakdown product of agaritine, an ingredient of the cultivated mushroom Agaricus bisporus. The implications of the findings are discussed.