. Author manuscript; available in PMC: 2015 Dec 1.

Published in final edited form as: Respir Physiol Neurobiol. 2014 Sep 19;0:147–159. doi: 10.1016/j.resp.2014.09.006

Table 2.

Values at baseline (Pre) and during exposure to gas challenge and return to room-air

Parameter	Variables	HX	HC	H-H
Frequency (breaths/min)	Pre	170 ± 9	173 ± 11	192 ± 11
	GC - max	380 ±14^*	388 ± 19^*	401 ± 21^*
	GC - 5 min	216 ± 8^*	308 ± 23	373 ± 16
	RA - max	364 ± 17^*	391 ± 20^*	428 ± 22^*
	RA - 15 min	262 ± 24^*	212 ± 18^*	226 ± 19
Rejection Index (%)	Pre	14 ± 2	14 ± 2	13 ± 2
	GC - max	45 ± 3^*	36 ± 4^*	43 ± 3
	GC - 5 min	14 ± 2	3 ± 1^*	8 ± 2^*
	RA - max	65 ± 6^*	33 ± 5^*	53 ± 4^*
	RA - 15 min	33 ± 3^*	23 ± 3^*	37 ± 4^*
(Rejection Index/Frequency) × 100	Pre	8 ± 1	8 ± 1	7 ± 1
	GC - max	12 ± 1^*	11 ± 1^*	11 ± 1^*
	GC - 5 min	6 ± 1^*	1 ± 0^*	2 ± 1
	RA - max	18 ± 2^*	10 ± 2	13 ± 2^*
	RA - 15 min	13 ± 2^*	11 ± 2	17 ± 1^*

The data are presented as mean ± SEM. GC, gas challenge. RA, return to room-air. HX, hypoxic-gas challenge. HC, hypercapnic gas challenge. H-H, hypoxic-hypercapnic gas challenge. There were 16 male C57BL6 mice in each gas challenge (mice only received one of the challenges).

P < 0.05, significantly different from Pre values.