BIOCHEMICAL ASSAY OF COLLAGEN AND ELASTIN IN THE NORMAL AND VARICOSE-VEIN WALL

Alterations of the connective tissue in the varicose vein wall have be en noted by several investigators; however, the cause of the vein dila tation has still not been established. The aim of this study was to fi nd a biochemical explanation to the development of varices by evaluati ng sensitive biochemical markers of collagen and elastin in the varico se vein wall. 4-L-Hydroxyproline (HYP), as a marker of collagen conten t, and desmosine (DES) and isodesmosine (IDES), as markers of elastin, were measured in 47 macroscopically dilated and 32 nondilated segment s of 20 varicose saphenous veins collected from 20 patients with varic es. The same measurements were made in 24 fragments of normal saphenou s veins collected from 14 patients in whom the vein was removed to be used for graft procedures. HYP (collagen) and DES and IDES (elastin) w ere determined with a colorimetric method and HPLC, respectively. ANOV A test was used to compare mean values (+/-SD). HYP and collagen conte nt were similar in varicose and normal veins. There was a significant reduction of both DES and IDES in dilated segments of varicose veins ( P < 0.05 vs normal veins and nondilated segments); the ratio of elasti n to collagen was lower in varicose than normal veins (P < 0.05), and this reduction was most significant in the dilated segments (P < 0.01 vs normal veins). These results suggest that dilatation of the varicos e vein wall may be related to some defect of elastin metabolism. Furth er studies on the metabolic activity of vein muscle cells are required . (C) 1996 Academic Press, Inc.