Endothelium-dependent relaxation of canine pulmonary artery endothelium after prolonged preservation. 
Experiments were designed to investigate the effect of Euro-Collins (EC) solution and University of Wisconsin (UW) solution on function of pulmonary arterial endothelium.  Third order canine pulmonary artery segments were preserved in cold (4 degrees C) UW (group 1, n = 8) or EC (group 2, n = 9) solutions for 16 hours.  The preserved (group 1 and 2) and control (group 3, n = 7) pulmonary arterial segments with and without endothelium were studied in vitro in organ chambers to measure isometric tension.  The endothelium-dependent relaxation to acetylcholine and adenosine diphosphate of group 1 and 3 were significantly better than those of group 2.  We concluded that endothelium-dependent relaxation of canine pulmonary arterial endothelium to receptor-dependent acetylcholine and adenosine diphosphate were impaired after preservation with Euro-Collins solution.  However, endothelium-dependent relaxation of pulmonary segments were well maintained after preservation with University of Wisconsin solution.