Membranous hydrolysis of saccharose (membranous digestion) and synthesis of invertase in the intestinal epithelial cells of rats and mice following introduction of pharmacological agents were studied. Ethyl alcohol, luminal and atropine lowered both the invertased activity in the area of membranous digestion and the synthesis of the enzyime. Hexonium and pilocarpine also lowered the level of membranous hydrolysis, but not the formation of enzymes. Epinephrine and octadine, on the contrary, enhanced the intensity of both these processes. The disclosed pharmacological effects are considered in the light of features specific for the structural organization of enzymes in the area of membranous digestion.