Table 2.

Effect of acute intermittent hypoxia on autonomic regulation of cardiovascular function and impact of bosentan

	Control		Bosentan		P Values
	Pre IH	Post IH	Pre IH	Post IH	IH	Drug	Interaction
MSNA burst frequency, bursts/min	21.0 ± 1.9	24.6 ± 2.6	24.6 ± 3.2	29.0 ± 3.1	0.03	0.04	0.81
MSNA burst incidence, bursts/100 heart beats	37.3 ± 2.9	42.5 ± 4.3	39.5 ± 4.5	49.2 ± 4.7	<0.01	0.17	0.19
Baroreflex sensitivity, bursts/100 heart beats/mmHg	−2.4 ± 0.3	−2.3 ± 0.3	−2.6 ± 0.2	−2.3 ± 0.2	0.46	0.53	0.39
Baroreflex sensitivity, ms/mmHg	14.5 ± 9.1	13.7 ± 4.8	11.2 ± 3.7	11.8 ± 4.6	0.92	0.11	0.53
T50, mmHg	69.7 ± 1.8	75.8 ± 1.9	66.2 ± 2.0	69.6 ± 2.2	<0.01	<0.01	0.23

Data are reported as means ± SE from n = 12 men unless noted (baroreflex sensitivity and T50, n = 9). Two-way repeated-measures ANOVA testing the main effect of IH (pre, post) and drug (control, bosentan) and the interaction of IH and drug (normality: Shapiro–Wilk, equal variance: Brown–Forsythe). Pairwise multiple comparison (Holm–Sidak). IH, intermittent hypoxia; MSNA, muscle sympathetic nerve activity. Bold type signifies P < 0.05.