SR33805

SR33805 (CAS No.: 121345-64-0) is a potent small-molecule calcium channel antagonist primarily targeting L-type Ca2+ channels, widely utilized in cardiovascular and smooth muscle biology research. It exhibits high affinity under both depolarized and polarized membrane conditions, with activity in the nanomolar range, and demonstrates selectivity for L-type over T-type calcium channels, indicating its utility in dissecting voltage-dependent calcium influx mechanisms. In vitro studies show that SR33805 inhibits growth factor-induced vascular smooth muscle cell proliferation in the low micromolar range in a dose-dependent manner, supporting its relevance in investigating cellular processes associated with vascular remodeling. In animal models, administration of SR33805 has been shown to reduce intimal hyperplasia following vascular injury without altering smooth muscle cell density, and to modulate excitation–contraction coupling in cardiomyocytes isolated from failing myocardium, including restoration of altered cell shortening dynamics without affecting calcium transient amplitude, suggesting an influence on myofilament calcium sensitivity. These properties make SR33805 a valuable experimental tool for studying calcium-dependent signaling pathways, cardiac excitation–contraction coupling, and vascular pathophysiology, with concentrations or dosing regimens varying according to specific experimental systems and study objectives.