Biochemical and Histological Analysis of Collagen and Elastin Content and Smooth Muscle Density in Normal and Varicose Veins

Abstract

Objective: Determination of the ratio of collagen and elastin to protein content of varicose/non-varicose veins from calf and determination of collagen, elastin and smooth muscle density of varicose/non-varicose vein walls. Design: Prospective study; control vein samples obtained from amputees for ischaemic vascular disease and varicose vein samples obtained from an equivalent Position following surgical stripping. Setting: Departments of Human Morphology and Vascular Surgery, Queen's Medical Centre, University of Nottingham, UK. Patients: Seven patients with no evidence of venous disease treated by amputation of the lower limb for vascular disease and 12 patients treated for varicose veins by ligation and stripping of the long saphenous vein. Interventions: Vein sections were examined biochemically and histologically using stereological techniques. Main outcome measures: Biochemical quanitfication of collagen, elastin and protein and stereological analysis of collagen, elastin and smooth muscle density of varicose and non-varicose veins. Results: There was no difference between the collagen/Protein or elastin/protein ratio in varicose and normal veins but there was a significant increase in muscle density with corresponding decrease in collagen and elastin density in the walls of varicose veins compared with non-varicose vein controls. Conclusions: There were no differences in the collagen or elastin content of varicose veins when compared with non-varicose veins. Smooth muscle hypertrophy occurs in varicose veins, which appears to disrupt the collagen/elastin lattice of the vein wall.

Smooth Muscle Changes in Varicose Veins: An Ultrastructural Study

“…Rose and Ahmed (1986) suggested that fibrous tissue invades muscle layers, disrupting their regular cellular pattern. While muscle hypertrophy in varicose vein walls with disorganization of connective tissue support has been suggested (Svejcar et al, 1963;Browse et al, 1988;Travers et al, 1992), others in contrast have reported muscle loss with replacement by fibrous tissue (Rose and Ahmed, 1986;Dovel, 1992). In this study, we observed wider muscle layer in the media of varicose sections, but the amount of smooth muscle was proportionately less than in control sections.…”

Intimal Changes in Varicose Veins: An Ultrastructural Study.

“…They proposed that a primary defect in the amount of collagen and elastin supporting an endothelium from the outside would lower resistance to venous pressure and presumably lead to dilatation. In contrast, Rose and Ahmad (1986) have shown that varicose vein walls have a higher than normal collagen content whereas Travers et al (1992) found no difference in the ratio of collagen to total protein between control and varicose veins. Contradictory evidence also exists on the pathology of smooth muscle cells (SMCs) in varicose veins.…”

An in Vitro Model for the Molecular Investigation of Varicose Veins: Use of Cultured Explants of Human Long Saphenous Vein

“…At a pathological level, primary VVs show thicker SMC layers in the intima and media when compared with normal veins [26,27], with SMC hypertrophy quite typical. However, a primary defect of SMCs per se is not thought to be the causative, underlying problem.…”

“…As with explants from normal veins, histological examination of samples of varicose LSV, taken at day 7 rather than being restricted to the internal and external elastic laminae [24,27]. Such disturbances of the wall and smooth muscle integrity may clearly help to account structurally for the localised dilatations and toruosities characteristic of VVs.…”