An in vitro model for the molecular investigation of varicose veins: Use of cultured explants of human long saphenous vein

Objective: To develop an in vitro model from explants of human varicose vei ns (VVs). Procedures: Segments of VVs were cultured for up to 14 days with 30% fetal calf serum. At 7 and 14 days, segments were analysed for changes in intima: media thickness and by immunohistochemistry. Comparisons were made with VVs at isolation and cultured explants of normal vein. Results: At isolation, VVs had a significantly thicker intima than normal v eins (p<0.001). By day 7 in culture, normal veins developed a significant ( smooth muscle cell-derived) 'neo-intima' (p<0.006). In contrast, in VVs the re was little change in the intima but a significant increase in the thickn ess of the media (p<0.001). Following 14 days in culture, both the neo-inti ma in normal veins and thickened media in VVs had regressed. Overall, there was a reduction in the intima:media ratio in VVs by day 14 (p<0.03). Conclusions: Segments of VVs can be maintained in culture for up to 14 days without developing a neointima and may provide a suitable model to investi gate mechanisms underlying the chronic venous insufficiency of varicosity.