第32章，作用与消化系统的药物.ppt

Chapter 32 Drugs acting on digestive system 作用于消化系统的药物 1.The principal pathogenesis of peptic ulcer --- helicobacter pylori ( Hp ) in adult population incidence of Hp infection: 50-80% pathophysiology §1. antipeptic ulcer drugs 2. associated pothogenesis: salicylate and other NSAIDs; psychological factors; endogenous histamine release; diet imbalance acid, pepsin, Hp mucus /bicarbonate; mucosal blood flow ; PGE2 ,PGI2 synthesis attack factors defensive factors Peptic ulcer occur The goals of therapy ↓clinical symptoms; promotion of healing（促进愈合） prevention of recurrence （防止复发） peptic ulcer antipeptic ulcer drugs 1. drugs eradicating Hp 2. antacides 3. reduce gastric acid secretion 4. mucosal protective drugs classification 祛邪扶正 I. antacids regulation of gastric acid secretion factors of ↑gastric acid secretion Gastrin (+) G-R Ach (+) M1-R Histamine (+) H2-R H+/K+ ATPase (+) proglumide pirenzepine ranitidine omeprazole gastric acid secrete inhibitors 西咪替丁 cimetidine 雷尼替丁 ranitidine 法莫替丁 famotidine 尼扎替丁 nizatidine 1). H2-receptor antagonists After a single dose ↓ gastric acid secretion ＞90% (basal and food-stimulated ); ↓ nocturnal(夜间的) secretion Used in DU and GU; Zollinger-Ellison syndrome . actions and uses pirenzipine 哌仑西平 1. selectively ㈠ gastric M1-receptor →gastric acid secretion↓ 2. only used with H2-R antagonists, especially in peptic ulcer with nocturnal pain. 2) M-R blocker proglumide 丙谷胺 1. competitive block gastrin receptor → the gastric acid secretion↓； Protecting gastic mucosa, promoting ulcer healing. 3) Gastrin-R blocker proton pump inhibitors, PPI 奥美拉唑 Omeprazole ( losec ); 兰索拉唑 lansoprazole; 泮托拉唑 pantoprazole; 雷贝拉唑 rabeprazole. 4) H+-K+ ATPase inhibitors combines with –SH of H+/K+ ATPase → irreversible inhibit H+ pump → H+ secretion ↓ hi