In order to assess the role of α7 nAChR signaling in RV fibrosis and dysfunction, we studied a rat PH model at 2 time points (3 and 7 weeks, Figure 1A) that develops severe PH (Figure 1B) with increased RV end diastolic pressure (Figure 1C), RV hypertrophy (Figure 1D), RV systolic and diastolic dysfunction (Figure 1, E and F, respectively), and reduced cardiac output (Figure 1G) in response to SU5416/hypoxia (SuHx) (8, 26). This evidence concerns the gene CHRNA7 and fibrosis.