心绞痛_1课件.ppt

Nitrates Endothelial cell NO Guanylyl cyclase* Guanylyl cyclase GTP cGMP GMP ↓ ↓ Ca2+ (intracellular) MLC-PO4 MLC Relaxation Contraction + Mechanisms of action Mechanisms of action cGMP Nitrates NO cGMP platelet PGI2; CGRP (降钙素基因相关肽) smooth muscle relaxation Clinical Uses Angina : all types Sublingual Acute myocardial infarction:iv Congestive heart failure (CHF) Pulmonary hypertension Adverse reactions 1.Response to vasodilation Flushed appearance Throbbing headache Orthostatic hypotension Tachycardia 2.Methemoglobinemia 3.Tolerance Probable mechanism: (1)Blood vessel tolerance: -SH depletion (2)Dilate blood vessels BP RAAS Management: (1)Dose (2)Interval:a nitrate-free period of at least 8 hours (3)Diet: (rich in -SH) (4)Composed with ACEI or diuretics 硝酸酯类药代动力学特点比较 药物 给药方法 一次用量 起效时间 持续时间 (mg) （分） （小时） 硝酸甘油 舌下 0.3~0.6 1~2 20~40分 口服 2.5 30 3-6 气雾吸入 0.4～0.8 2～5 10~30分 贴片 10～20 30～60 24 硝酸异山梨酯 舌下 5~10 15~30 2~4 口服 10 15~30 2~4 单硝酸异山梨酯 口服 20 45~60 8～10 Nitroglycerin Isosorbide dinitrate Isosorbide mononitrate Section III β-adrenoceptor Blockers Nonselective β-blokers: Propranolol, Pindolol, Timolol Selective β1-blokers: Atenolol, Metoprolol, Acebutolol Antianginal effects 1. Decrease myocardial oxygen consumption β- R blockage → contractility and HR ↓ → myocardial oxygen consumption↓ β- R blockage → end-diastolic volume and ejection time ↑→ myocardial oxygen consumption↑ Net effect: myocardial oxygen consumption↓ Antianginal effects 2. Improve blood su