Carbazeran citrate is a selective phosphodiesterase III (PDE III) inhibitor primarily used in pharmacological research for its cardiotonic effects. It is employed in studies investigating cardiovascular function, particularly in models of congestive heart failure, where it enhances myocardial contractility, improves hemodynamics, and promotes vasodilation without significantly increasing heart rate. Researchers utilize it to explore the mechanisms underlying heart failure, blood pressure regulation, and vascular smooth muscle relaxation, aiding in the development of potential therapeutic agents for cardiovascular diseases such as hypertension and ischemic heart conditions.