PULMONARY ENDOTHELIAL-CELL FUNCTION AFTER MODIFIED EUROCOLLINS SOLUTION INFUSION

Eurocollins solution is commonly used in preparation for lung transpla ntation and is known to increase the pressure cost of perfusion by cau sing both vascular obstruction and increased tone. In this study we as sessed whether Eurocollins solution had a direct effect on the pulmona ry endothelial cell by causing increased permeability or by depressing its metabolic integrity. The effect of 4-degrees-C Eurocollins soluti on on transvascular fluid flux properties and on, angiotensin-converti ng enzyme function were assessed. Eurocollins solution had no effect o n the microvascular filtration coefficient or on the critical capillar y pressure, both very sensitive indicators of the permeability charact eristics of the endothelium. The inert angiotensin-converting enzyme s ubstrate H-3!BPAP had a peak metabolism of 83% and 81%, respectively, and an average metabolism of 82% both before and after Eurocollins so lution infusion. The first order enzyme rate constant, Vmax/Km, was, h owever, reduced by 22% with Eurocollins solution perfusion. Eurocollin s solution does not therefore cause increased endothelial permeability and hence a permeability type of pulmonary edema. The reduced first o rder rate constant of the enzyme, in the presence of normal peak and a verage metabolism, may be partially accounted for by a reduction in in travascular surface area available for enzyme substrate interaction.