MOA of Verapamil is:
Ans: A (Inhibition of Ca+2 channel) "Verapamil blocks L type Ca2+ channel & delays their recovery"- KDT 6th/517Classification of Antiarrhythmic Drugs: four classesClass 1 action is sodium channel blockade(Membrane stabilizing drugs)Class 2 action is sympatholytic Drugs with this action reduce b-adrenergic activity in the heart.Class 3 action is manifest by prolongation of the APD. Most drugs with this action block the rapid component of the delayed rectifier potassium current, 1Kr.Class 4 action is blockade of the cardiac calcium current.Class IV agents act by blocking voltage-sensitive calcium channels. Class IV drugs in therapeutic use as antidysrhythmic drugs (e.g. verapamil) act on L-type channels. Class IV drugs slow conduction in the SA and AV nodes where action potential propagation depends on slow inward Ca2+ current, slowing the heart and terminating SVT by causing partial AV block. They shorten the plateau of the action potential and reduce the force of contraction. Reduced Ca2+ entry reduces after-depolarisation and thus suppresses premature ectopic beats.
Inhibition of Ca+2 channel
Inhibition of Na-t-channel
Inhibition of K+ channel
Block membrane repolarisation
Anti-Hypertensive