IMPAIRED ENDOTHELIAL PROSTACYCLIN PRODUCTION OF THE CANINE VEIN GRAFTIN A POOR DISTAL RUNOFF LIMB

Background. Because blood flow modulates endothelial prostacyclin prod uction, the extent of this production in autologous vein grafts implan ted in poor distal runoff limbs needed to be examined. Methods. Endoth elial prostacyclin production in canine autologous vein grafts was mea sured in poor distal runoff limbs (poor runoff group) and compared wit h findings in normal runoff limbs (control group). Vein grafts were pe rfused in a closed circuit at 3 days and 1, 2, 3, and 4 weeks after im plantation; after perfusion for the first 30 minutes in a steady flow (basal prostacyclin production), the grafts were exposed to arachidoni c acid (stimulated prostacyclin production) for the following 30 minut es. Prostacyclin, as the metabolite 6-keto-PGF1alpha, was radioimmunoa ssayed. Results. Basal and stimulated prostacyclin production increase d in both groups during a period of time after implantation. At 2 week s when endothelialization was complete, prostacyclin production in the poor runoff group was impaired, compared with the findings in the con trol group, and this difference increased with time. At 4 weeks the st imulated prostacyclin production was 18.91 +/- 4.03 ng/cm2 in the cont rol group and 11.60 +/- 1.67 ng/cm2 in the poor runoff group (p < 0.05 ). Conclusions. We propose that the impaired capacity of the vein graf t to produce prostacyclin in a poor distal runoff may lead to loss of graft patency in reconstructed arteries.