Fig 8. A proposed molecular mechanism for HTR2B antagonism to prevent heritable PAH.

Mutations in the tail domain of BMPR2 result in increased SRC transport and signaling. Antagonism of HTR2B inhibits the translocation of SRC and decreases SRC signaling, causing a decrease in expression of SRC regulated genes. Functionally, this results in increased small vessel compliance, reduced inflammatory infiltrate, and decreased vascular smooth muscle contractility which together contribute to a restoration in mean pulmonary arterial pressures.