Propranolol has which of the following effects?

Question

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[III E 2, 3; Table 3.1]. Propranolol, a $\beta$-adrenergic antagonist, blocks all sympathetic effects that are mediated by a $\beta_{1}$ or $\beta_{2}$ receptor. The sympathetic effect on the sinoatrial (SA) node is to increase heart rate via a $\beta$ receptor; therefore, propranolol decreases heart rate. Ejection fraction reflects ventricular contractility, which is another effect of $\beta_{1}$ receptors; thus, propranolol decreases contractility, ejection fraction, and stroke volume. Splanchnic and cutaneous resistance are mediated by $\alpha_{1}$ receptors.

Propranolol Has Which of the Following Effects