Nicardipine mechanism of action?

Nicardipine is a dihydropyridine calcium channel blocker. Its mechanism is:

- It blocks L-type ( Cav1.2 ) voltage-gated calcium channels in vascular smooth muscle cells.
- This reduces Ca2+ influx during depolarization, lowering intracellular calcium.
- Lower Ca2+ decreases activation of the calmodulin–MLC kinase pathway, causing relaxation of smooth muscle.
- Result: arteriolar (mostly arterial) vasodilation → reduced systemic vascular resistance and afterload, lower blood pressure.
- Effects on veins are minimal; reflex tachycardia can occur due to the BP drop.
- Nicardipine also increases coronary vasodilation, improving coronary blood flow.
- It has relatively greater vascular selectivity compared with non-DHP calcium channel blockers.