ATTENUATION OF NEUTROPHIL AND ENDOTHELIAL ACTIVATION BY INTRAVENOUS MORPHINE IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION

To investigate the effects of morphine on neutrophil and endothelial a ctivation, we measured serum levels of intercellular adhesion molecule -1 (ICAM-1), L-selectin, and neutrophil endopeptidase 24.11 (NEP) in 3 8 patients with acute myocardial infarction (group 1) and 16 control s ubjects (group 2). In group 1, all the patients underwent blood sampli ng at initial presentation and 10 minutes later. Twenty of them had 3 mg of morphine administered intravenously immediately after the first sampling (group 1A) and the other 18 after a second sampling (group 1B ). The serum levels of ICAM-1 and L-selectin were both significantly h igher in groups 1A and 18 than in group 2. In group 1A, the ICAM-1 dec reased significantly at second blood samplings (310 +/- 28 vs 368 +/- 30 ng/ml; p < 0.001), whereas in group 18 there was no significant cha nge in ICAM-1 (357 +/- 33 vs 359 +/- 26 ng/ml; p = NS). In group 1A, t he L-selectin decreased significantly at second blood samplings (2.3 /- 1.2 mg/L, p < 0.001 vs baseline), whereas in group 18 there was no significant change in L-selectin (3.9 +/- 1.0 mg/L, p = NS vs baseline ). There was no significant difference in baseline NEP activities betw een groups 1A and 1B (4.89 +/- 1.22 vs 5.14 +/- 1.57 nmol/mg protein; p = NS). However, the NEP activities at second blood samplings decreas ed significantly in group 1A (9.88 +/- 1.86 nmol/mg protein, p < 0.001 vs baseline), whereas no significant changes were observed in group 1 B (5.09 +/- 1.62 nmol/mg protein, p = NS vs baseline). In conclusion, morphine increased NEP activities and thus attenuated shedding of L-se lectin and ICAM-1. (C) 1997 by Excerpta Medica, inc.