UNIVERSITY-OF-WISCONSIN SOLUTION EFFECTS ON INTIMAL PROLIFERATION IN CANINE AUTOGENOUS VEIN GRAFTS

This study was carried out to investigate if the University of Wiscons in solution (UWs) is suitable for long-term preservation of autogenous vein grafts (AVG) prior to transplantation, compared to autologous wh ole blood (AWB) and normal saline (NS). Autogenous jugular and femoral veins were harvested from adult mongrel dogs, using a ''no-touch'' te chnique. One segment of vein was immediately implanted to serve as a c ontrol, while other segments were stored for 24 hr at 4 degrees C in A WB, NS, or UWs. The control and the preserved veins were implanted as reversed interposition grafts in the common carotid or femoral artery positions. After 6 weeks, scanning electron microscopy revealed an int act endothelial cell monolayer in all vein grafts that was stained pos itively for factor VIII. The degree of intimal thickening, as assessed by light microscopy in the middle position of the grafts, was similar in controls (52.0 +/- 15.8 mu m) and in veins stored in UWs (58.5 +/- 16.1 mu m), but it was significantly increased (P < 0.05) in veins pr eserved in NS (198.9 +/- 19.5 mu m) and in AWE (312.0 +/- 171.6 mu m). Isometric tension studies revealed that maximum contraction and sensi tivities (assessed by EC(50),) to norepinephrine were significantly re duced (P < 0.05) in AVG stored in AWB (0.05 +/- 0.02 g/mm(2) and 5.5 /- 2.8 mu M), but not in UWs (0.16 +/- 0.03 g/mm(2) 0.92 +/- 0.34 mu M ) and NS (0.09 +/- 0.03 g/mm(2) and 3.0 +/- 1.1 mu M), compared with c ontrols (0.17 +/- 0.03 g/mm(2) and 0.99 +/- 0.38 mu M). Acetylcholine (Ach)-induced maximum relaxations were similar in all of the veins. Ho wever, vessels stored in AWE were found to be more sensitive (P < 0.05 ) to Ach (0.004 +/- 0.002 mu M) than those stored UWs (0.042 +/- 0.018 mu M. Sodium nitroprusside produced similar responses in all of the v eins. These data demonstrated that storage of veins in UWs for 24 hr p rior to transplantation is more suitable than storage in AWB and NS fo r preserving the morphology and functional integrity of the smooth mus cle and endothelium. (C) 1995 Academic Press, Inc.