Fig. 4.
Isolated pulmonary vascular smooth muscle cells (VSMCs) of CH piglets show increased Ca2+ current density. A: patch-clamp recordings of Ca2+ current in freshly isolated pulmonary VSMCs from 21-day N and CH piglets. Constant holding potential was −70 mV. Currents were elicited by 8-mV depolarizing steps from −70 mV to +50 mV (top traces). Nifedipine (5 μmol/l) reduced current amplitude in both preparations (bottom traces). B: current-voltage relationships show an increased CaL channel current density in VSMCs of CH compared with N piglets (n = 5, 10). *Significant difference (P < 0.05) between N and CH values obtained at the same voltage.