Table 2.

Baseline small pulmonary artery inner diameter and fura-2 ratios as well as in situ fura-2 calibrations after intraluminal pressurization to 12 mmHg

	ASIC1+/+ Group		ASIC1−/− Group
	Control	CH	Control	CH
Baseline inner diameter, μm	131 ± 9	118 ± 8	123 ± 12	141 ± 9
Baseline fura-2 ratio, F340/F380	0.56 ± 0.02	0.66 ± 0.03*	0.55 ± 0.04	0.67 ± 0.05*
Low calibration, F340/F380	0.43 ± 0.02	0.42 ± 0.04	0.43 ± 0.03	0.42 ± 0.03
High calibration, F340/F380	1.11 ± 0.16	1.16 ± 0.16	0.92 ± 0.12	1.03 ± 0.19

Data are expressed as means ± SE; n = 11–14 animals depending on the group. For in situ calibrations, fura-2 ratios were collected from arteries at the end of the experiment by incubation with the Ca²⁺ ionophore ionomycin (10 μM) in either Ca²⁺-free or normal physiological saline solution (1.8 mM CaCl₂) for low and high calibration, respectively. CH, chronic hypoxia; F₃₄₀/F₃₈₀, 340-to-380-nm fluoresence ratio.

^*P < 0.05 vs. the corresponding control group.