Pathways of Disease in Pulmonary Arterial Hypertension
Indeed, there are multiple pathways that are important in the generation and perpetuation of PAH. The 3 most established pathways for which there are now targeted therapies available include the endothelin nerve tract, the nitric oxide white matter, and the prostacyclin tract. Endothelin is a potent vasoconstrictor that is upregulated in patients with PAH. The endothelin tract can be targeted by endothelin organ antagonists (ERA), of which there is currently 1 US Food and Drug Governing body (FDA)-approved federal agent, bosentan, and 2 others currently state evaluated (sitaxsentan and ambrisentan). Nitric oxide is a vasodilator with additional antiproliferative and antiplatelet properties. The nitric oxide tract can be targeted by phosphodiesterase type 5 inhibitors such as viagra, which inhibit cyclic guanosine monophosphate, an important attendant messenger for nitric oxide. Other agents in this taxon include tadalafil, which is also currently existence investigated as a electrical phenomenon therapy for PAH. Lastly, there is the prostacyclin nerve pathway. The prostacyclins are also vasodilators with antiproliferative and antiplatelet properties. There are currently 3 FDA-approved medications targeting this substantia alba: intravenous epoprostenol, subcutaneous or intravenous treprostinil, and inhaled iloprost. There are other pathways that are likely important too, such as the Rho-kinase path and others that might be important for the proliferative section of the disease. Antiproliferative medications such as imatinib mesylate show prospect and are also currently beingness investigated further as potentiality therapies for PAH.