PHGY 210 Lecture Notes - Lecture 7: Helicobacter Pylori, Gastric Mucosa, Stomach
27 Nov 2015
School
Department
Course
Professor
Document Summary
Secreted throughout the g. i. by: surface epithelial cells, cardiac and pyloric glands, mucous neck cells (fundus and corpus) Gastric mucosal barrier (gmb: the most important defense is the impermeability of the surface epithelial cells and the tight junctions that don"t allow the h ions to penetrate. It is a physiological barrier: penetration by h ions could give rise to erosions or ulcers in the stomach. Presence of gastrin-producing tumours present in stomach or pancreas. Both neural and hormonal regulation for gastric secretion at the level of the stomach. Vagus and sympathetic regulation for neural mechanisms. Gastrin, histamine, and somatostatin are hormonal agents that regulate the secretion of acid. Cephalic phase - psychic and gustatory (vagally-mediated: operates through stimulation of enteric neurons by the vagus, neural regulation. Distension activates enteric neurons going to all the different secretory cells in the stomach. Vagus can also activate enteric neurons causing secretion from all the different secretory cells in the stomach.
