In vitro effects of low level yellow laser irradiation on human red blood cells

The study of human blood by laser is beneficial because of its availability, and physiological importance. This study is conducted to investigate the effects of low level laser (LLL) doses on human red blood cells. The effects of exposure to yellow low level laser (X = 589 nm) on human blood are observed. A 10 mW laser was used for irradiation with a fluence rate of 30 mW/cm
²
. The pathological blood samples were collected into EDTA containing tubes and each sample was divided into two equal aliquots used as control and for irradiation. The aliquot was subjected to laser irradiation at different exposure times in order to deliver different dose. The blood parameters HGB, HCT, MCV, MCH, MCHC, RDW-SD, and RBC counts are measured immediately after irradiation using a computerized hemtoanalyzer. Irradiation with doses 72 J/cm
²
and 90 J/cm
²
was observed to induce significant decreases in RBC volume, P<;0.0001 and P<;0.003 respectively. The highest response has been observed with the dose 72 J/cm
²
, with an exposure time of 40 min. It can be suggested that LLL can reduce RBC volume due to the increased free intracellular Ca+2 concentrations which activates Ca+2dependent K+channels with consequent K+ ion efflux and cell shrinkage.