Fig. 3

Rescue of PH in middle-aged female ApoE-deficient mice by exogenous estrogen replacement therapy. a Experimental protocol showing middle-aged female ApoE-defeicent mice receiving either a single injection of phosphate buffered saline (PBS) for CTRL group at day 0, or single injection of monocrotaline (MCT, 60 mg/kg) for PH group, or single injection of monocrotaline (MCT, 60 mg/kg) at day 0 followed by estrogen (E2) treatment from day 21 to 30 in E2 group. b–c Bar graphs showing RVSP (mmHg), and RV hypertrophy index (Weight ratio of RV/LV + IVS) for ApoE-deficient middle-aged female mice in CTRL (n = 4), PH (n = 4), and E2 (n = 4) treated groups. *p < 0.05 vs. CTRL, #p < 0.05 vs. PH. d Immunofluorescence images for pulmonary vascular remodeling comparing medial hypertrophy in middle-aged female ApoE-deficient mice of PH group and E2 treated group. e Quantification of arteriolar wall thickness for vessels less than 50 μm in MA ApoE-deficient mice in PH (n = 3) and in E2 (n = 4) groups. *p < 0.05 vs. PH (t test). Expressed as mean ± SEM