PDE5A and pulmonary arterial hypertension: Although it is well published that elevated levels of PDE5 enzyme are associated with underlying pathological processes of the disease, we observed no significant deterioration in cardiac functions nor histological features of WGLL-treated animals when compared to the PAH group (as seen in Figure 1 and Figure 2 and Table 2), which can be partly explained by the fact that many other signaling pathways are involved in molecular pathogenesis of pulmonary arterial hypertension [63,64,65].