Isorey Mechanism of Action

Pharmacotherapeutic group: Vasodilators used in cardiac diseases, organic nitrates. ATC Code: CO1D A08.
Pharmacology: Pharmacodynamics: Mechanism of Action and Pharmacodynamic effects: Isosorbide dinitrate is an organic nitrate and vasodilator. It decreases left and right ventricular end-diastolic pressures to a greater extent than systemic arterial pressure, resulting in reduced cardiac afterload and, particularly, preload.
Isosorbide dinitrate enhances oxygen delivery to ischemic myocardium by promoting redistribution of blood flow through collateral channels and from epicardial to endocardial regions via selective dilation of large epicardial vessels.
Isosorbide dinitrate reduces myocardial oxygen demand by increasing venous capacitance, leading to peripheral venous pooling and a consequent reduction in ventricular volume and myocardial wall tension.
Pharmacokinetics: Metabolism and Elimination: Isosorbide dinitrate (ISDN) is eliminated from plasma with a short half-life of approximately 0.7 hours. Its metabolic degradation, similar to that of other organic nitrates, occurs primarily through denitration and glucuronidation. The rate constants for metabolite formation are approximately 0.57 h^-1 for isosorbide-5-mononitrate (IS-5-MN), 0.27 h^-1 for isosorbide-2-mononitrate (IS-2-MN), and 0.16 h^-1 for isosorbide (IS).
Both IS-5-MN and IS-2-MN are pharmacologically active primary metabolites. IS-5-MN undergoes further metabolism to isosorbide-5-mononitrate-2-glucuronide (IS-5-MN-2-GLU), which has a shorter half-life (approximately 2.5 hours) compared to IS-5-MN (approximately 5.1 hours). Among these compounds, ISDN has the shortest half-life, while that of IS-2-MN (approximately 3.2 hours) is intermediate.