PMN lung infiltration and Src and eNOS activation are partially dependent on ICAM-1. (A) Carrageenan-induced Src and eNOS activation was partially dependent on ICAM-1 expression. Tyrosine phosphorylation of Src at Y418 and serine phosphorylation of eNOS at S1177 were reduced in carrageenan-treated ICAM-1^−/− mice. (B) Enhanced basal lung ICAM-1 expression in eNOS^−/− mice was further induced on carrageenan treatment. #P < .05 versus sham eNOS^−/−; *P < .05 versus sham WT. (C) PMN lung infiltration induced by 4-hour carrageenan was reduced in ICAM-1^−/− mice. (D) Carrageenan-induced PMN infiltration in the lung (after 4 hours) was reduced in eNOS^−/− mice. PMN infiltration in the lung was determined by measuring MPO activity. (C-D) Data are mean ± SD (n = 5). *P < .05 (WT versus ICAM-1^−/− or eNOS^−/−) of the fold increase over sham treatment.