Vessel wall modification in venous pathology. Application to the study of phlebotonic drugs.

Pathophysiological investigation of varicose veins show extensive metabolic perturbation and structural parietal changes. Oxygen consumption is reduced more than three-fold while levels of activity of proteolytic enzymes from lysosomes are significantly raised. Connective tissue in the venous wall undergoes profound deterioration, with a decrease in collagen fibrils and an increase in proteoglycans. Recent studies of venous endothelial cells in hypoxia have provided an etiological explanation for these disorders. These disturbances in the venous wall are of a magnitude sufficient to produce defectable changes in serum and urine of patients with varicose veins. All the foregoing data provide a basis for a pharmacological approach allowing an improved understanding of the mechanism of action of phlebotonics and the selection of the most active agents.