Cinética de lise mecânica de eritrócitos humanos e sua associação com variáveis bioquímicas, hematológicas e oxidativas em indivíduos saudáveis e em indivíduos com diabetes mellitus tipo 1

Abstract

The transport of gases by the erythrocyte depends on its ability to undergo membrane changes before the action of external forces, as occurs during the passage through capillaries smaller than its diameter. The ability of the erythrocyte to resist to these tensions is a property called mechanical stability. This study proposes a method, based on kinetic formalism of Michaelis-Menten, for determining the erythrocyte mechanical stability from the kinetics of mechanical hemolysis. For this, we have built a device consisting of a controlled intensity rotor coupled to a propeller capable of transmitting rotational shock forces by contact with the test solution and the mechanical agitation of the solution molecules. The tests were performed with a fixed speed of 8,000 rpm. The curves obtained in these tests were adjusted by a non-linear hyperbolic curve, in order to determine the erythrocytes half-life time (t1/2) and the maximum absorbance (Amax) associated to complete hemolysis. To examine whether these constants, which showed good inter-subject variability, have physiological meanings, they were correlated with biochemical and hematologic variables that are associated with the composition and behavior of erythrocytes. The Amax values showed positive correlations with RBC, Hb, Ht, MCV, MCH and MCHC. The t1/2 values showed significant positive correlations with total cholesterol (t-C) and triglycerides (TGC), a borderline positive correlation with the LDL-C levels, and a negative significant correlation with RDW.