藥理學(xué)PPT課件第十五章影響自體活性物質(zhì)藥物

1、藥理學(xué)PPT課件第十五章影響自體活性物質(zhì)藥物Histamine and Antihistamine Agents目的了解組胺與變態(tài)反應(yīng)的關(guān)系。掌握抗組胺藥H1、H2受體拮抗劑的作用與應(yīng)用。Histamine and Antihistamine Agents內(nèi)容組胺：來源，內(nèi)源性組胺與過敏反應(yīng)的關(guān)系，作用，為診斷用藥。H1、H2受體的劃分。Histamine and Antihistamine Agents內(nèi)容抗組胺藥：H1受體阻斷劑：對(duì)H1受體的阻斷作用。中樞作用及其它。臨床用途，主要不良反應(yīng)。苯海拉明、異丙嗪（非那根）、氯苯那敏（撲爾敏）、布克利嗪（安其敏）。H2受體阻斷劑：對(duì)H2受體的阻斷

2、作用。西米替?。浊柽溥桑┑囊炙嶙饔?，對(duì)消化性潰瘍病的評(píng)價(jià)，不良反應(yīng)。Histamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsHistamineIntroductionHistamine is biologically active amine that is found in many tissue (such as mast cells or basophils ),has complex ph

3、ysiologic and pathologic effects, and is often released locally. Together with endogenous peptides, prostaglandins and leukotrienes, and cytokines, they are sometimes called autacoids or local hormonesHistamine receptor subtypesReceptor SubtypeDistributionPostreceptor MechanismH1Smooth muscle, endot

4、helium, brain IP3,DAGH2Gastric mucosa, cardiac muscle, mast cells, brain cAMPH3Presynaptic: brain, myenteric plexus, other neuronsG protein-coupledHistamine receptor subtypesReceptor SubtypeEffects after being activatedH1 bronchoconstriction and contraction of intestinal S.M. Expand blood vessel Per

5、meability stimulate sensory nerve endingsH2 Cause gastric acid, gastric pepsin and intrinsic factor production. Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate.Histamine receptor subtypesReceptor SubtypePartially Selective AgonistsPartially Selective Antagonist

6、sH12-(m-Flurophenyl)-histamineDiphenhydramine, promethazine, astemizoleH2Dimaprit, impromidine, amthamineCimetidine, ranitidineH3R-MethylhistamineThioperamideHistaminePharmacodynamics Secretory tissue Smooth muscle Cardiovascular system The “triple response”Receptor SubtypeEffects after being activa

7、tedH1 bronchoconstriction and contraction of intestinal S.M. Expand blood vessel Permeability stimulate sensory nerve endingsH2 Cause gastric acid, gastric pepsin and intrinsic factor production. Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate. The “triple resp

8、onse” 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.HistamineHistamineClinical use of histamine To be used in testing gastric acid secretion and diagnosis of leprosy.

9、Decrease of gastric acid can be seen in malignant anemia and true achlorhydiaHistamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsPhysiologic antagonists EpinephrineRelease inhibitors CromolynHistamine receptor antagonists H1

10、receptor antagonists H2 receptor antagonistsHistamine AntagonistsHistamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsH1 receptor antagonistsChemistryFirst-generation blockersDiphenhydramine, promethazine, astemizoleSecond-gen

11、eration blockers Cimetidine, ranitidinerapidly absorbed orallywidely distributed and the first-generation drugs enter the CNS readily.Most metabolized in the liver Most excreted from the kidneyPharmacokineticsH1 receptor antagonistsPharmacodynamics Histamine Receptor Blockade CNS Inhibition Antichol

12、inoceptor action and Local anesthesiaReceptor SubtypeEffects after being activatedH1 bronchoconstriction and contraction of intestinal S.M. Expand blood vessel Permeability stimulate sensory nerve endingsH2 Cause gastric acid, gastric pepsin and intrinsic factor production. Cause a decrease in systo

13、lic and diastolic blood pressure and a increase in heart rate.H1 receptor antagonists Allergic Reaction Nausea and Vomiting Sedation and hypnogenesisClinical UsesToxicity Sedation, antimuscarinic action, drug allergy, cardiac arrhythmias (astemizole) and possible teratogenic effects.H1 receptor anta

14、gonistsHistamine and Antihistamine AgentsHistamine and its agonistsHistamine antagonistsH1 receptor antagonistsH2 receptor antagonistsH2 receptor antagonistsChemistry & PharmacokineticsCimetidineRanitidineFamotidineNizatidineH2 receptor antagonistsPharmacodynamicsAcid secretion and gastric motilityC

15、ardiovascular systemimmunological regulationReceptor SubtypeEffects after being activatedH1 bronchoconstriction and contraction of intestinal S.M. Expand blood vessel Permeability stimulate sensory nerve endingsH2 Cause gastric acid, gastric pepsin and intrinsic factor production. Cause a decrease in systolic and diastolic blood pressure and a increase in heart rate.H2 receptor antago