南开大学 医学院张京玲 王侃 代红胜Histamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsHistamine Together with endogenous peptides,prostaglandins and leukotrienes,and cytokines,they are sometimes called autacoids or local hormones bronchoconstriction and contraction of intestinal S.M.Expand blood vessel Permeabilitystimulate sensory nerve endings Cause gastric acid,gastric pepsin and intrinsic factor production.Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate.bronchoconstriction and contraction of intestinal S.M.Expand blood vessel Permeabilitystimulate sensory nerve endings Cause gastric acid,gastric pepsin and intrinsic factor production.Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate.Intradermal injection of histamine causes a characteristic wheal-and-flare response,which involves an erythema,an edematous wheal and a red irregular flare surrounding the wheal.To be used in testing gastric acid secretion and diagnosis of leprosy.Decrease of gastric acid can be seen in malignant anemia and true achlorhydiaHistamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsHistamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsFirst-generation blockersSecond-generation blockers urapidly absorbed orallyuwidely distributed and the first-generation drugs enter the CNS readily.uMost metabolized in the liver uMost excreted from the kidney bronchoconstriction and contraction of intestinal S.M.Expand blood vessel Permeabilitystimulate sensory nerve endings Cause gastric acid,gastric pepsin and intrinsic factor production.Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate.Sedation,antimuscarinic action,drug allergy,cardiac arrhythmias(astemizole)and possible teratogenic effects.Histamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonists bronchoconstriction and contraction of intestinal S.M.Expand blood vessel Permeabilitystimulate sensory nerve endings Cause gastric acid,gastric pepsin and intrinsic factor production.Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate.Gastrointestinal reaction,CNS reaction,Endocrine system reactionCytochrome P-450 inhibition。