Effect of dl-ethionine and naturally occurring amino acids on adrenal necrosis induced by 7,12-dimethyl-benz [alpha]anthracene and its 7-hydroxymethyl derivative in female Sprague-Dawley rats.

-Ethionine at a dose of 125 mg. i.p. 3 days and, to a lesser extent, 4 days before i.v. treatment with 3 mg. 7,12-dimethylbenz[]anthracene (DMBA) protects the adrenal glands from the adrenocorticolytic action of the polycyclic hydrocarbon in female Sprague-Dawley rats. Treatment of rats less than 3 days or more than 4 days before DMBA challenge has no protective effect. -Methionine at the same dose as ethionine is not protective when given 3 days before DMBA but shows some protective action as a 1-day pretreatment. The protective action of ethionine seems unrelated to the suppression of protein synthesis or to the production of fatty liver. With both methionine, and ethionine, protection of adrenal glands is correlated with the marked vacuolation of the cytoplasm of hepatocytes. Administration of methionine at the same dose as ethionine abolishes the protective action of the latter when they are given 3 days before DMBA. Glycine, like methionine, also protects when given from about the same time as DMBA to 24 hr. beforehand. Its protective action can be prevented by concomitant administration of large doses of arginine. None of the aforementioned protective treatments were effective against adrenal necrosis induced by 7-hydroxymethyl-12-methylbenz[]anthracene.