Section 3 B-Adrenoceptor blockers Mechanism of action: 1.Antagonize the sympathetic nerve activity ①↓damage on cardiac muscle from CA ②↓renin,↓RAS,↓cardiac load ③↑B-R,come back the transmit ability ④↑sensitivity of B-R to catecholamines 2.Antioxidation blocking a-R carvedilol 3.Antiarrhythmia and improve myocardial ischemiaSection 3 Section 3 β-Adrenoceptor Adrenoceptor blockers blockers Mechanism of action: 1. Antagonize the sympathetic nerve activity ①↓damage on cardiac muscle from CA ②↓renin , ↓RAS，↓ cardiac load ③↑β-R，come back the transmit ability ④↑sensitivity of β-R to catecholamines 2. Antioxidation , blocking α1 -R — carvedilol 3. Antiarrhythmia and improve myocardial ischemia