Produção de Pepsina: Onde Acontece e Por Que Importa para a Digestão

Pepsin, the enzyme that initiates protein digestion, is secreted as inactive pepsinogen by gastric chief cells in the fundus and body of the stomach. Gastric acid (pH <4) activates it to pepsin, which then breaks down proteins in the stomach lumen.

Critically, pepsin is not present in the small or large intestine. Once chyme enters the duodenum, pancreatic proteases (trypsin, chymotrypsin) and brush-border peptidases take over. Pepsin is inactivated at the higher pH (>6) of the intestinal environment.