The nonessentiality of the hypophysis for the induction of tumors with 3,4-benzpyrene.

Abstract

Summary 1.Twenty hypophysectomized rats were given injections subcutaneously of a single dose of 3,4-benzpyrene. Twelve intact control rats were similarly treated. All the intact controls developed tumors. 2.Seven hypophysectomized rats died without tumors prior to the 93d day before any of the controls showed tumors. One hypophysectomized animal died without a tumor on the 117th day. The remaining twelve animals all developed tumors between the 106th and the 174th day. 3.Tumors grew at a considerably slower rate in the hypophysectomized animals than in the controls, averaging 28.2 gm. as against an average of 108 gm. in the controls. 4.It is concluded that the hypophysis is nonessential for the production of neoplasms with 3,4-benzpyrene.