Final answer:
Diltiazem (Cardizem) operates through calcium channel blockade, not via beta-adrenergic receptor blockade, ACE inhibition, or alpha-adrenergic receptor stimulation. It belongs to the class of Calcium Channel Blockers, which relax muscles and reduce blood pressure by impeding calcium ion movement.
Step-by-step explanation:
The mechanism of action of diltiazem (Cardizem) is c. Calcium channel blockade. Diltiazem is part of a class of medications known as Calcium Channel Blockers, which includes drugs like amlodipine (Norvasc, Lotrel), felodipine (Plendil), nifedipine (Adalat, Procardia), nimodipine (Nimotop), nisoldipine (Sular), and verapamil (Calan, Verelan). These medications work by hindering the influx of calcium ions through voltage-gated calcium channels in the cardiac and smooth muscle cells, which leads to relaxation and vasodilation, thereby lowering blood pressure and reducing cardiac workload.
Calcium channel blockers differ from beta-blockers, which act on beta-adrenergic receptors blocking adrenaline, reducing heart rate and blood pressure. They also differ from drugs such as ACE inhibitors and ARBs, which act on the renin-angiotensin system. Calcium channel blockers specifically impede the movement of calcium ions and do not exhibit beta-adrenergic receptor blockade, inhibition of ACE, or alpha-adrenergic receptor stimulation.