Human digestive system the esophagus at its upper end and to the duodenum at its lower end. Gastric acid (informally "gastric juice"), produced in the stomach plays a vital role in the digestive process, and mainly contains hydrochloric acid and sodium chloride. A peptide hormone, gastrin, produced by G cells in the gastric glands, stimulates the production of gastric juice which activates the digestive enzymes. Pepsinogen is a precursor enzyme (zymogen) produced by the gastric chief cells, and gastric acid activates this to the enzyme pepsin which begins the digestion of proteins. As these two chemicals would damage the stomach wall, mucus is
National Digestive Diseases Information Clearinghouse Publications produced by the Clearinghouse are carefully reviewed by both NIDDK scientists and outside experts. National Digestive Diseases Information Clearinghouse The National Digestive Diseases Information Clearinghouse (NDDIC) is an information dissemination service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The NIDDK is part of the National Institutes of Health, which is under the U.S. Department of Health and Human Services. Established in 1980, the Clearinghouse provides information about digestive diseases to people with digestive disorders and to their families, health care professionals, and the public. The NDDIC answers inquiries, develops and distributes publications, and works