Relative variation to received dose of some erythrocytic and leukocytic indices of human blood as a result of low-level laser radiation: An in vitro study

Objective: This study investigated the in vitro effects of low-level laser radiation (LLLR) on selected theologic constants of the human blood. The va riations of CBC parameters to the received dose were determined, as well as of blood viscosity (an erythrocyte aggregation index), as a research metho d for some structural alteration of blood proteins. This was also confirmed by the electrophoretic study of plasma proteins from the irradiated blood. Methods: Fresh blood samples (whole blood) from 16 adult regular blood don ors were irradiated with a He-Ne laser (lambda = 632.8 nm; power output = 6 nM; mean irradiance on blood samples approximate to 180 mW . cm(-2); beam spot diameter approximate to 2 mm), operating in continuous wave. Doses ran ged between 0 (control sample) and 9.346 J.cm(-3). EDTA (for CBC and viscos ity measurements) or citrate (for electrophoresis) anticoagulant was used. Measurements were performed before (control samples) and after irradiation. In most of the cases, the measurements mere made immediately after irradia tion. In some cases, the measurements were made after 23 or 48 h after irra diation, respectively, to conclude whether the modifications caused from ir radiation occur in time, or immediately after irradiation. Results: followi ng irradiation, marked variations of some erythrocyte and leukocyte indices and changes of the erythrocyte aggregation (viscosity), as a function of r eceived dose, were observed. Significant differences between control and ir radiated blood samples mere found for the following rheologic factors: RBC tin 22.2% of cases); HGB (26.8%); BCT (82.4%); MONO and GRAN (36.7%); visco sity (82.5%). From the plasma proteins: albumin (22.2%); alpha I globulin a nd gamma globulin (18.5%); fibrinogen (70.4%). In most of the cases, remark able effects (maxima) mere noticed around 1.2 J.cm(-3) dose value. We consi der this dose value as optimal, one that can lead to beneficial effects. Th e cell membrane integrity was not affected from irradiation, for doses betw een 0 and 9.346 J.cm(-3), and will probably not even be affected at higher doses (see MCV and MCHC behavior). Conclusions: The effect of LLLR on red b lood cells confirms the nonresonant mechanism of this biostimulating effect , by the changes occurring in the cell membrane (in our case, blood cells!, by revitalizing of red blood cell functional capacities and by several bio chemical effects at the membrane's level. These are to be studied thoroughl y in future studies. The physical-biochemical and biological effects caused by LLLR on blood can influence the physical-chemical parameters needed for the long-term storage of blood products. These effects can also lead to a quicker revitalization of the erythrocyte membrane (which nas subjected to the action of some physical and biochemical factors during the preservation process), to perform its oxyphoric function in transfusion procedures.