Manidipine

Contraction of vascular smooth muscle is stimulated by Gq coupled receptors which produce calcium release from the sarcoplasmic reticulum. This is followed by opening of voltage dependent calcium channels and an influx of calcium into the cell ultimately producing contraction. Manidipine binds to and dissociates slowly from L- and T-type voltage dependent calcium channels on smooth muscle cells, blocking the entrance of extracellular calcium into the cell and preventing this contraction. This produces vasodilation which decreases blood pressure. Manidipine produces renal vasodilation and an increase in natriuresis. This likely contributes to the antihypertensive effect by reducing blood volume. Manidipine is selective for the vasculature and does not produce significant effects on the heart or central nervous system at clinically relevant dosages.