What is the primary action of calcium channel blockers in treating hypertension?

Calcium channel blockers primarily treat hypertension by causing vasodilation, which is achieved through the inhibition of calcium influx into vascular smooth muscle. Calcium plays a pivotal role in muscle contraction; when calcium channels are blocked, the smooth muscle in the arterial walls relaxes, resulting in dilation of the blood vessels. This leads to a decrease in peripheral vascular resistance, thereby lowering blood pressure.

This mechanism is effective in managing hypertension because vasodilation not only reduces blood pressure but also helps alleviate the workload on the heart. Therefore, calcium channel blockers are commonly used in the treatment regimen for patients with high blood pressure, allowing for improved blood flow and reduced risk of cardiovascular complications.

In contrast, the other choices do not accurately represent the primary mechanism of action for calcium channel blockers. Increasing heart rate by stimulating beta receptors is more characteristic of beta-agonists. Promoting sodium excretion in the kidneys pertains more to diuretics than to calcium channel blockers. Lastly, while reducing arterial elastic recoil is related to the overall function of blood vessels, it does not directly encompass the primary action of calcium channel blockers in lowering blood pressure.