心得安的主要作用是拮抗性地阻滞β—肾上腺素能受体,临床上有关的受体包括心脏、血管、支气管平滑肌和肾小球旁体的β—受体。心得安的最明显效应是心脏的去交感神经化,其程度视药物的剂量而定。服用心得安后,呈现心动过缓、房室传导减慢;如果原有交感作用,则心肌被抑制。心排出量减少,由于血压不下降,因而周围血管阻力增加。心得安阻止肾上腺素能的扩张支气管,然而,如无支气管阻塞性疾患,则对气道阻力无影响。血浆肾素活性降低,但在无高血压时并不显著影响血压或钠潴留。心得安的所有这些作用均可被注射异丙基肾上腺素 Prednisone’s primary role is to block the beta-adrenergic receptor antagonist, clinically relevant receptors including the heart, blood vessels, bronchial smooth muscle and glomerular paracrine β-receptor. The most obvious effect of propranolol is the de-sympathetic nature of the heart, depending on the dose of the drug. After taking security experience, showing bradycardia, atrioventricular conduction slowed down; if the original sympathetic effect, the myocardium is inhibited. Cardiac output decreased due to blood pressure does not decline, so the increase in peripheral vascular resistance. Adrenaline is prophylactic to prevent the adrenergic expansion of the bronchi, however, in the absence of bronchial obstruction, it has no effect on airway resistance. Plasma renin activity is reduced but does not significantly affect blood pressure or sodium retention without hypertension. All of these effects of propranolol can be injected with isoproterenol