Efeito da concentração salina sobre a estabilidade de eritrócitos humanos em soluções de etanol

Abstract

NaCl is a classic osmoregulatory agent that in isotonic conditions with the plasma is able to stabilize the red blood cells (RBC) in a relaxed (R) state, where these cells congregate a certain degree of stability with the capacity of exercise properly all its functions. The ethanol is a classic chaotropic agent, capable of promoting denaturation, but is also an osmolyte, able to promote stabilization of RBC. In 0.9% w/v NaCl and between 0 and 24% v/v ethanol, the RBC suffer lysis, but between 24 and 32%, the RBC are stabilized by the action of ethanol. This stabilization forms compacted or tight (T) RBC, which lost however many cell functions. In this work we studied the effect of concentrations of NaCl at 0.5, 0.9 and 1.1% w/v on the fixed time incubation (30 min) of human blood with concentrations of ethanol between 0 and 32%v/v. The RBC lysis and stabilization transitions by ethanol were described by sigmoids and characterized by their lysis half-point (D50) and stabilization (S50) transitions, respectively, and also by the amplitude (dX) and height (h) of those curves. The average value of D50 increased from 12.61 to 14.29%, but fell back again to 13.97% of ethanol/100 mL of 0.5, 0.9 and 1.1% w/v NaCl, respectively. The average value of S50 fell from 27.26 to 26.22 and 25.99% of ethanol/100 mL of solution with the increase in the concentration of NaCl solution of 0.5 to 0.9 and mL of 1.1% w/v saline, respectively. These results indicate that hypertonic saline solution potentiated the stabilizing effect of ethanol, certainly moving the RBC from of the state R to the state T.