Figure 3.
Augmented depolarization-dependent pulmonary arterial constriction after CH is prevented by cholesterol repletion. (A–D) Vasoconstriction in response to KCl (% baseline inner diameter) and vessel wall [Ca2+]i (F340/F380) in pressurized, Ca2+-permeabilized, endothelium-disrupted arteries from CH and control rats under conditions of cholesterol repletion (A and B), cholesterol depletion with MβCD (C and D), or after administration of their respective vehicles. Vessel wall [Ca2+]i (F340/F380) was not different between groups/treatments and was unaltered by depolarizing concentrations of KCl after Ca2+ permeabilization, confirming Ca2+-clamp conditions. Values are means ± SE of n = 4–5 rats/group. *P < 0.05 CH vehicle or CH MβCD versus the control group. #P < 0.05 CH cholesterol versus CH vehicle. B = baseline fura-2 (F340/F380) fluorescence.