Table 3.

Ex vivo contractile and relaxant responses in arterial rings isolated 6 and 24 h after instillation of rats with diesel exhaust particles (DEP) or saline

	phenylephrine		acetylcholine		sodium nitroprusside		isoprenaline
	logEC50	Max (% response to KCl)	logIC50	Imax (% preconstriction)	logIC50	Imax (% preconstriction)	logIC50	Imax (% preconstriction)
Aorta
6 h
saline	-7.24 ± 0.14	67.1 ± 8.1	-7.88 ± 0.20	94.9 ± 1.3	-8.67 ± 0.13	96.7 ± 1.0	-7.52 ± 0.15	90.0 ± 1.8
DEP	-7.03 ± 0.07	88.6 ± 5.1*	-7.75 ± 0.11	96.1 ± 1.4	-8.70 ± 0.11	87.9 ± 1.0	-8.07 ± 0.10*	93.1 ± 2.2
24 h
saline	-7.29 ± 0.13	120.8 ± 14.5	-7.52 ± 0.10	99.3 ± 0.5	-8.43 ± 0.13	99.3 ± 0.6	-7.62 ± 0.16	88.0 ± 5.8
DEP	-7.38 ± 0.11	115.3 ± 13.0	-7.67 ± 0.17	96.2 ± 1.5	-8.60 ± 0.10	98.9 ± 0.4	-7.62 ± 0.26	87.8 ± 6.4
Femoral Artery
6 h
saline	-5.59 ± 0.08	115.1 ± 24.2	-6.69 ± 0.11	68.9 ± 4.9	-7.80 ± 0.15	94.1 ± 2.9	-6.39 ± 0.29	67.3 ± 7.1
DEP	-5.53 ± 0.06	91.8 ± 4.0	-6.81 ± 0.14	77.2 ± 5.6	-7.81 ± 0.18	95.1 ± 1.9	-6.51 ± 0.27	77.4 ± 3.9
24 h
saline	-5.46 ± 0.24	136.0 ± 32.4	-6.79 ± 0.18	61.2 ± 4.7	-7.64 ± 0.18	92.7 ± 2.7	-7.03 ± 0.14	41.8 ± 4.8
DEP	-5.46 ± 0.09	124.2 ± 11.4	-6.86 ± 0.14	68.3 ± 6.3	-7.81 ± 0.18	92.5 ± 2.2	-7.07 ± 0.23	58.7 ± 6.5
Mesenteric Artery
6 h
saline	-6.02 ± 0.15	96.1 ± 3.6	-7.29 ± 0.27	76.4 ± 7.8	-7.82 ± 0.15	98.1 ± 2.2	-8.19 ± 0.17	101.3 ± 0.7
DEP	-5.76 ± 0.19	99.3 ± 3.9	-7.51 ± 0.11	88.4 ± 3.6	-8.36 ± 0.05**	98.3 ± 1.4	-8.80 ± 0.24	99.6 ± 1.2
24 h
saline	-6.19 ± 0.11	103.6 ± 5.9	-7.65 ± 0.23	82.0 ± 5.0	-8.40 ± 0.15	99.1 ± 1.1	-8.74 ± 0.16	102.4 ± 0.9
DEP	-6.07 ± 0.11	132.9 ± 13.1	-7.58 ± 0.17	80.6 ± 5.8	-8.28 ± 0.19	99.3 ± 3.4	-8.32 ± 0.21	102.5 ± 0.4

Results are mean ± SEM (n = 5-10), obtained by non-linear regression

*P < 0.05, **P < 0.01, control vs DEP, unpaired t-test.

EC₅₀ - concentration producing 50% of maximum contraction

E_max - maximum contraction

IC₅₀ - concentration producing 50% of maximum vasodilatation

I_max - maximum vasodilatation