Table 3.

Excess vasocontraction (in %) induced by N'-monomethyl L-arginine (L-NMMA, 0.10 mM) after PGF_2α precontraction (1 μM) in aorta segments from ApoE^-/- mice after intratracheal instillation of TiO₂ particles or control solution (90% saline and 10% BAL fluid).

Exposure i.t. instillation	Drug	- tempol	+ tempol
Control	L-NMMA	17.0 ± 2.84	11.3 ± 1.08
fTiO2		10.2 ± 1.49	14.3 ± 2.62
pTiO2		14.4 ± 2.89	13.2 ± 2.21
nTiO2		12.4 ± 1.65	15.9 ± 3.67

The measurements were done in both absence and ex vivo presence of the SOD mimic, tempol. Data are expressed as means ± SEM (n = 10-11).