Affiliations: National Technical University of Athens, Department of Physics, Biophysics Unit | National Technical University of Athens, Department of Electrical and Computer Engineering, Biomedical Engineering Unit
Abstract: It is well known that there is a correlation between cardiovascular diseases and catecholamines release on the one hand and that catecholamines induce changes on the deformability of red blood cells (RBCs) on the other. In addition He-Ne laser low-power irradiation, seems to decrease RBC deformability and to increase their osmotic fragility in vitro. The present work aims to estimate the effects of low-power He-Ne laser irradiation on red blood cells deformability, with and without epinephrine, in order to give some more information about the biophysical mechanisms of interaction of He-Ne laser irradiation with RBCs, through the modification of epinephrine and RBCs membrane interaction. In this study a low-power He-Ne laser (power output 8.0 mW, 632.8 nm wavelength) was used for the irradiation of red blood cells in the presence or absence of epinephrine. Deformability of individual cells passing through micropores was determined by measuring the change of electrical resistance produced by the erythrocytes travelling via a specific polycarbonate filter containing 30 non-overlapping pores (15 μm in length, 5 μm in diameter) without significant variations of pore size (less than 2%). The data obtained indicate that: 1) The RBCs deformability was increased by 6.2% and 13% in the presence of 10−4 M and 10−3 M epinephrine respectively, as reflected in a significant decrease (p=0.025) in the mean transit time <τ> of RBCs passing through the pores. 2) The RBCs deformability was decreased by 30%, due to low-power He-Ne irradiation, for 5 min. 3) RBCs in the presence of 10−4 M epinephrine after He-Ne irradiation for 5 min under continuous stirring presented a decrease of 21.7% in deformability and in the presence of 10−3 M epinephrine a decrease of 11.8% in deformability. The results indicate that epinephrine and laser irradiation act antagonistically in relation to RBCs deformability.
Keywords: Red blood cells, Helium-Neon laser, Deformability, Catecholamines
