MOA OF ANTIANGINAL DRUG

Question 1

MOA of nitrate

Answer 1

Nitrate
↓
Release NO
↓
stimulate guanyly cyclase
↓
↑↑cGMP
↓
de phosphorylation of myosin light chain (MLCK)
Decrease Ca++ concentration
↓
Relaxation of vsm

Pharmacological action
Venodilation. Arteriolar dilation dilation of coronary vessel

Venodilator arteriolar
↓. ↓pvr↓afterload
Pooling of blood
↓ venous return
↓preload
↓end diastolic vol
↓ cardiac workload

Dilation of coronary vessel
↑ BF ↑ O2 delivey

All together relief anginal pain

Question 2

MOA OF BETA# and CCB

Answer 2

Beta# - B1 of heart- ↓HR ↓FOC ↓workload ↓O2 consumption

CCB -block Volta sensitive L type Ca++ channel by binding to a1 subunit

Question 3

MOA of k+ channel opener

Answer 3

NICORANDIL→release NO - ↑CGMP
↓. ↓
K+ efflux
↓
Hyperpolarization. ↓
Arteriolar+ venodilation. ↓
↓preload & ↓afterload. Relax vsm

Question 4

MOA of Ranolazine, trimetazidine,ivabradine,dipyridamole

Answer 4

Ischaemia - ca++ influx
Derive energy by FA metabolism

Ranolazine- ↓ late inward Na+ current in myocardium ↓ ca++ influx
Inhibit fatty acid oxidation

Trimetazidine↓ FA oxidation ↑ glucose consumption

Ivabradine act in SA node ↓ HR

Dipyridamole- coronary steal phenomenon by ↑ BF to non ischemic part