单硝酸异山梨酯 (Imdur, Ismo, Monoket)

概览

Isosorbide mononitrate is a nitrate used to prevent and treat angina and to treat angina caused by coronary artery disease.

作用机制

Isosorbide mononitrate acts as a prodrug for nitric oxide (NO), which is a potent vasodilator gas that is released when the drug is metabolized. NO activates soluble guanylyl cyclase in vascular endothelial cells, which increases the intracellular concentrations of cyclic GMP (cGMP). cGMP activates cGMP-dependent protein kinases, such as protein kinase G and I, which activates the downstream intracellular cascades. The downstream cascade results in reduced intracellular concentrations of calcium, caused by processes including inhibition of IP-mediated pathway, phosphorylation of big calcium-activated potassium channel leading to cell hyperpolarization and reduced calcium influx, and increased calcium efflux via the Ca2+-ATPase-pump. Reduced intracellular calcium concentrations lead to the dephosphorylation of myosin light chains and the relaxation of smooth muscle cells.

适应症

Isosorbide mononitrate is indicated for the prevention and management of angina pectoris due to coronary artery disease. The onset of action of oral isosorbide mononitrate is not sufficiently rapid to be useful in aborting an acute anginal episode.

• Angina Pectoris