Fig. 1

Experimental protocol used to establish the MCT21 and MCT28 models. A, MCT21 model: pulmonary and carotid arteries were catheterized 21 days after the MCT or saline injection; awake mean pulmonary artery pressure (mPAP) and mean artery pressure (mAP) were measured at day 22 when rats were fully awake; lung and heart samples were obtained for measurements of the right ventricle (RV) weight-to-left ventricle + septum (LV + S) weight ratio (RV/LV + S), morphometry of pulmonary arteries, Western blotting and PCR after the pressure measurements. B, MCT28 model: measurement of systolic right ventricular pressure (sRVP) under anesthesia and sampling for RV/LV + S, Western blotting and PCR were performed 28 days after the injection of MCT or saline. Sal/CLZ-, rats injected with saline and fed rat chow without cilostazol (CLZ); Sal/CLZ +, rats injected with saline and fed rat chow with CLZ; MCT/CLZ-, rats injected with MCT and fed rat chow without CLZ; MCT/CLZ +, rats injected with MCT and fed rat chow with CLZ. MCT, monocrotaline; Sal, saline; n =, number of rats used. We were not always successful in obtaining all these datasets or samples for each assigned rat because of technical reasons, especially when recording mPAP, and thus the number of rats used (n) was not always the same as the numbers listed in Figs. 5, 6, and 9