mice have less acute pulmonary vasoconstriction than WT controls. (A) Immediate percent increase of RVSP in response to 0.1 ug/kg IV of U-46619. (B) Increase in RVSP after 5, 10, and 15 minutes of acute hypoxia in WT (gray line) and TSP-1-/- mice (black line). * = p < 0.05 vs. WT. # p < 0.05 vs. WT at 15 minutes.