HEMORRHAGE AND RESUSCITATION ALTER THE EXPRESSION OF ICAM-1 AND P-SELECTIN IN MICE

Acute inflammatory lung injury is a common clinical occurrence followi ng blood loss and trauma, and is characterized by massive neutrophil i nfiltration into the lung. In order to better examine cell trafficking that may contribute to lung injury in this setting, we investigated i n vivo mRNA levels and immunohistochemically determined expression of the adhesion molecules P-selectin and the intercellular adhesion molec ule (ICAM)-1 in murine lungs over the 3-day period following hemorrhag e and resuscitation. Significant increases in P-selectin mRNA levels w ere present in lungs obtained 3 days after hemorrhage. ICAM-1 mRNA lev els were significantly increased 6 and 72 hr after hemorrhage. Immunoh istochemical staining for P-selectin was enhanced on pulmonary vascula r endothelium in all visible vessels at 6, 24, and 72 hr after hemorrh age. ICAM-1 immunoreactivity was significantly increased on the alveol ar epithelium at 6 and 72 hr post-hemorrhage. These results suggest th at increased expression of adhesion molecules in the lung at early pos t-hemorrhage timepoints may contribute to neutrophil infiltration into the lungs and the frequent development of acute lung injury following blood loss and trauma. (C) 1995 Wiley-Liss, Inc.