Aorto-porto-caval micro-rheological differences of red blood cells in laboratory rats: Further deformability and ektacytometrial osmoscan data

Abstract

Investigation of regional hemorheological properties are important in ischemia-reperfusion experimental surgical and microsurgical research models, however, the physiological arterio-venous as well as porto-caval differences in erythrocyte deformability and aggregation are still controversial. In this study, besides measuring blood pH, blood gases, lactate concentration and hematological parameters we determined erythrocyte deformability (rotational ektacytometer) together with osmoscan data as well as erythrocyte aggregation (light transmittance aggregometer) in blood samples taken from the portal vein, caudal caval vein and abdominal aorta of rats. Blood pH, partial blood gas pressures showed the anticipated physiological differences. Leukocyte count was lower in arterial blood; hematocrit, erythrocyte and platelet count was higher in systemic and portal venous blood. The lowest elongation index values were measured in arterial blood, the highest in venous and portal venous blood showed values in between. The osmoscan data did not show important differences. Erythrocyte aggregation M index 5 s showed the lowest values in arterial, higher in systemic venous and portal venous blood samples. M index 10 s showed significantly low values in systemic venous blood. M1 values were slightly higher in arterial blood compared to venous blood but the highest were in portal venous blood. Erythrocyte deformability and aggregation may show aorto-porto-caval differences in the rat. The appropriate control examinations thus are important in experimental surgical and microsurgical research models.