Following hypophysectomy of the rat, partial involution occurs in the zymogenic cells of the stomach (Baker and Abrams, '54), parotid gland (Baker and Abrams, '55), pancreas (Baker and Pliske, '57) , submandibular gland (Lacassagne and Chamorro, '40 ; Grad and Leblond, '49) , and in the intestinal cells of Paneth (Baker, Kent and Pliske, in press). Insofar as they have been studied, enzyme synt...