. 2010 Aug 31;588(Pt 21):4235–4247. doi: 10.1113/jphysiol.2010.196402

Table 1.

Fetal arterial blood gas status

		Normoxia		Acute hypoxaemia			Recovery

		N0	N75	H5	H15	H30	R30	R60
		Saline infusion or Treatment with vitamin C (± NO clamp)
pH_a	Saline Infusion	7.36 ± 0.01	7.36 ± 0.01	7.36 ± 0.01	7.34 ± 0.01	7.29 ± 0.01^a	7.32 ± 0.01^a	7.34 ± 0.01
	Vitamin C infusion	7.35 ± 0.01	7.29 ± 0.01^a,^b	7.28 ± 0.01^a,^b	7.25 ± 0.01^a,^b	7.21 ± 0.01^a,^b	7.25 ± 0.02^a,^b	7.28 ± 0.01^a,^b
	Vitamin C infusion and NO clamp	7.35 ± 0.01	7.28 ± 0.01^a,^b	7.26 ± 0.01^a,^b	7.23 ± 0.01^a,^b	7.19 ± 0.01^a,^b	7.21 ± 0.01^a,^b	7.24 ± 0.01^a,^b
(mmHg)	Saline infusion	54.7 ± 0.7	54.8 ± 0.6	53.7 ± 0.6	54.1 ± 0.5	54.2 ± 0.6	54.3 ± 0.7	55.1 ± 0.5
	Vitamin C infusion	56.0 ± 0.5	56.3 ± 0.8	55.8 ± 0.7	56.0 ± 0.6	54.7 ± 0.7	54.6 ± 0.6	55.3 ± 0.5
	Vitamin C infusion and NO clamp	55.3 ± 0.8	56.2 ± 0.5	54.5 ± 0.6	54.5 ± 0.7	55.2 ± 0.3	55.7 ± 0.6	55.0 ± 0.9
(mmHg)	Saline infusion	22.0 ± 0.8	21.3 ± 0.6	10.8 ± 0.3^a	11.4 ± 0.2^a	11.4 ± 0.2^a	21.2 ± 0.8	21.1 ± 0.8
	Vitamin C infusion	21.2 ± 1.0	21.2 ± 0.5	11.3 ± 0.3^a	11.3 ± 0.2^a	12.0 ± 0.3^a	21.2 ± 1.4	22.2 ± 1.5
	Vitamin C infusion and NO clamp	21.7 ± 0.9	21.0 ± 0.8	11.7 ± 0.4^a	11.7 ± 0.2^a	11.2 ± 0.2^a	20.7 ± 1.0	22.0 ± 1.5
Sat Hb (%)	Saline infusion	56.3 ± 1.4	53.5 ± 1.4	25.4 ± 1.3^a	25.2 ± 1.6^a	25.8 ± 0.9^a	53.2 ± 2.1	52.4 ± 2.1
	Vitamin C infusion	54.8 ± 1.9	53.3 ± 2.0	24.1 ± 1.2^a	23.2 ± 1.3^a	23.9 ± 1.4^a	53.0 ± 2.1	53.8 ± 2.3
	Vitamin C infusion and NO clamp	52.8 ± 3.4	51.6 ± 2.9	24.2 ± 1.3^a	23.9 ± 1.4^a	23.8 ± 1.5^a	50.7 ± 4.3	51.4 ± 4.6

Values are means ±s.e.m. at 0 (N0) and 75 min (N75) of normoxia, at 5 (H5), 15 (H15) and 30 min (H30) of hypoxemia, and at 30 (R30) and 60 min (R60) of recovery for fetuses exposed to 0.5 h of hypoxaemia during saline infusion (n = 7), treatment with vitamin C alone (n = 7) or treatment with vitamin C during the NO clamp (n = 7). Significant differences:

P < 0.05, vs. time period N0

P < 0.05, vs. saline infusion (two-way RM-ANOVA with Tukey's post hoc test).

pH_a, arterial pH; Inline graphic , arterial partial pressure of CO₂; , arterial partial pressure of O₂; Sat Hb, percentage saturation of haemoglobin with oxygen.