Healthy BM prevents the development of right heart disease in CAV-1 KO mice. Naive CAV-1 KO or WT BM was transplanted into naive CAV-1 KO mice, and mice were monitored for spontaneous development of PH. Naive WT mice were used as an additional control for normal aging. All mice were analyzed 11 months posttransplant. (A) Schematic representation of the experimental setup. (B) Pulmonary vessel density was measured on lung tissue sections stained for the endothelial cell marker CD31. CD31 area/total lung tissue area was quantified, showing that WT BM was not able to inhibit endothelial remodeling in CAV-1 KO mice. (C) Quantification of RV hypertrophy according to Fulton index [right/(left + septum) ventricular weight] demonstrated that WT BM blocked RV hypertrophy in CAV-1 KO mice. (D) Measurement of RVSP by SPR-1000 Mikro-Tip Catheter in the RV showed that RVSP was not elevated in CAV-1 KO mice transplanted with WT BM. (E) RV fibrosis visualized by trichrome staining showed reduced fibrosis in CAV-1 KO mice transplanted with WT BM. Original magnification ×20. (F) Quantification of the RV fibrosis by measuring trichrome area/total RV area. Each group contained male and female mice (5 mice total in each group). Mean ± standard error are shown. ANOVA values show differences across groups.