多糖類による赤血球集合現象 代用血しょうの問題点

Abstract

The effect of plasma substitutes composed of polysaccharides on the velocity of erythrocyte aggregation was examined with a rheoscope combined with a video camera, an image analyser and a computer, and the mechanism of polysaccharide-induced erythrocyte aggregation was studied.1) Dextran (Mw 40, 000 and Mw 70, 000) and hydroxyethyl starch (Mw 200, 000) in plasma substitutes increased the velocity of erythrocyte aggregation in 60% diluted plasma. The accelerating effect was marked in the high molecular weight dextran. The accelerating effect by dextran was less in glucose than in saline or lactate Ringer's solution.2) The velocity of erythrocyte aggregation became maximum at an optimal concentration of dextran. The optimal concentration was lower in higher molecular weight dextran, but was not affected by shear rate.3) The aggregation induced by high molecular weight dextran (Mw 70, 400) was inhibited by low molecular weight dextrans (Mw 43, 900 and Mw 10, 300), disaccharides (sucrose, maltose and isomaltose) and glucose. The aggregation induced by fibrinogen, IgG and plasma was affected by low molecular weight dextrans.4) The aggregation induced by pullulan (Mw 70, 000; linear polysaccharide) was more marked than that induced by dextran (Mw 70, 400; branched polysaccharide).5) The mechanism of polysaccharide-induced erythrocyte aggregation was discussed, and the suitable prescription for plasma substitutes was proposed from the rheological point of view.