What is the mechanism of action for calcium channel blockers?

What is the mechanism of action for calcium channel blockers?

• A. Inhibition of neurotransmitter release
• B. Blockage of voltage-gated calcium channels
• C. Inhibition of adrenergic receptors
• D. Increase in intracellular calcium

Answer: (B)

Calcium channel blockers primarily function by blocking voltage-gated calcium channels, which are crucial for the influx of calcium ions into various cell types, especially in cardiac and smooth muscle tissues. When these channels are inhibited, the entry of calcium into the cells is reduced. This results in decreased calcium concentration inside the cells, leading to several physiological effects, such as vasodilation, decreased myocardial contractility, and reduced conduction velocity through the heart. By preventing calcium from entering the cells, calcium channel blockers effectively lower blood pressure and relieve conditions such as angina and certain arrhythmias. The mechanism is particularly important in how these drugs exert their therapeutic effects, making them valuable in the management of cardiovascular diseases.

Calcium channel blockers primarily function by blocking voltage-gated calcium channels, which are crucial for the influx of calcium ions into various cell types, especially in cardiac and smooth muscle tissues. When these channels are inhibited, the entry of calcium into the cells is reduced. This results in decreased calcium concentration inside the cells, leading to several physiological effects, such as vasodilation, decreased myocardial contractility, and reduced conduction velocity through the heart.

By preventing calcium from entering the cells, calcium channel blockers effectively lower blood pressure and relieve conditions such as angina and certain arrhythmias. The mechanism is particularly important in how these drugs exert their therapeutic effects, making them valuable in the management of cardiovascular diseases.