Inhibition of Azo Dye Carcinogenesis by Adrenalectomy and Treatment With Desoxycorticosterone Trimethylacetate.

Summary 1) Feeding of a semi-synthetic diet containing 0.058 percent 3-methyl-paradimethylaminoazobenzene (3′-Me-DAB) to intact rats for four months resulted in liver enlargement and development of large neoplastic nodules in 100 percent of the cases. 2) Ad lib. or restrictive feeding of azo dye were equally effective in inducing liver carcinogenesis. 3) Treatment of dye-fed, intact rats with large doses of desoxycorticosterone trimethylacetate (DCT), over a 4-month period, had no effect on liver carcinogenesis. 4) Treatment of dye-fed, totally adrenalectomized rats for 4 months with large doses of DCT prevented marked liver enlargement and inhibited development of macroscopic lesions and neoplastic nodules. 5) The presence of small amounts of adrenal cortical tissue allowed the carcinogenic process to proceed in rats fed azo dye and treated with large doses of DCT.