Mdivi-1 and P110 decrease mitochondrial Drp1 expression in both control and PAH right ventricles (RVs) following ischemia reperfusion injury (IR). Immunoblots of RV tissue show translocation of Drp1 to the mitochondria was increased in MCT versus control RVs (PBS = saline). At baseline (before IR) there is increased mitochondrial Drp1 in MCT RVs, indicating elevated basal rates of fission. Mitochondrial Drp1 expression increased in both PBS and MCT RVs in an ex vivo RV Langendorff, ischemia-reperfusion injury model. Both Mdivi-1 and P110, a proposed peptide inhibitor of the interaction between Fis1 and Drp1, reduced the translocation of Drp1 to the mitochondria, though only significantly in MCT RVs with IR. n = 3~5/group. MCT, monocrotaline. * p < 0.05 vs. PBS-No IR; # p < 0.05 vs. MCT-No IR; $ p < 0.05 vs. MCT-IR. Reproduced with permission from Tian et al. [82].