Kinetics of electroinduced pores as a probe of membrane modification produced by ionizing radiation

Abstract

In this work, we have attempted to demonstrate that the study of erythrocyte electroporation can be used to characterize modifications induced at the membrane level by the exposure of living cells to ionizing radiation. Wistar rats were contaminated by chronic ingestion of tritiated water (HTO) in a range of absorbed doses between 0 and 49 cGy. Erythrocyte suspensions were subjected to single electrical pulses and, by modelling the time evolution of light absorption at 610 nm, kinetic parameters describing the electroporated suspension were calculated. A significant increase in the apparent haemolysis rate was observed for the irradiated erythrocytes when subjected to long, high-intensity electrical pulses. In milder electropulsation conditions, when the reversible electroporation process was favoured, the irradiated erythrocytes showed a significant increase in both the radius pore resealing rate and the maximum area of the electroporated surface (for a dose of 49 cGy) compared with the control. The results indicate that the modifications of the parameters due to the effects of irradiation on the erythrocytes reflect an increase in the membrane fluidity without disturbing the association between the cytoskeleton and membrane proteins.