Importance of fractional determination of plasma fibrinogen

Abstract

Heterogeneity of fibrinogen molecule in plasma is one of important phenomena in the research of thrombotic disorders. The purpose of this study is to clarify the neecssity of the clinical observation on the fibrinogen heterogeneity in plasma. Venous blood was sampled from 136 healthy persons and 31 cerebrovascular pltients into 3.8% sodium citrate (1:9). Total fibrinogen (TF) and high molecular weight fibrinogen (FI) were determined by the recently developed method using 2.3M glycine with various ionic strength. Low molecular weight fibrinogen (FII) was shown as the difference between TF and FI, and FII/FI was calculated. In healthy subjects, TF and FI increased with advancing age. The level of FII and FII/FI in patients were higher than those in healthy subtects. FII/FI in patients elapsed 13 months or above was higher than those elapsed 3 months or below. In comparison between healthy subjects and patients with 400mg/dl or below, the level of FII and FII/FT were also higher in patients. Patient's FII/FT was inversely proportional to F. XIII-A level determined by Laurell's immunoelectrophoresis. These results comfirm the importance of the fractional observation of plasma fibrinogen separated by molecular weight and clinical usefulness of the glycine precipitation method in the observation of plasma fibrinogen.