Influence of rose bengal on platelet aggregation activity

The goal of the study is to comparatively examine the effect of photoactivated rose bengal on platelet aggregation in vitro and in circulating blood of male Wistar rats. Platelet-rich plasma (PRP) was obtained from venous blood. The aggregation activity of platelets was determined by the turbidimetric method, the aggregation inducer was ADP at a final concentration of 1.25 μM. Rose bengal (RB) (Acros Organics, USA) was used as a photosensitizer (PS). PRP samples containing the PS were irradiated using ALOD-Izumrud laser (OOO “Alcom Medica”, Russia), λ = 532 nm, power density 0.05 W/cm2 , energy density of 6, 12 and 24 J/cm2 . The effect of photoactivated RB on the aggregation of circulating PLT was studied after laser irradiation of the femoral artery of the rats: 30 mW laser power, 2 mm spot diameter and 30 min exposure. RB at concentrations of 0.5 and 1 μg/ml was found to stimulate, and 5-10 μg/ml—to inhibit platelet aggregation. Photoactivation of RB weakens the stimulating effect of laser irradiation on the aggregation of platelets. Photodynamic modification of blood led to an increase in the in[1]tensity of platelet aggregation by 24% in comparison to the control group, and by 39.6% compared to the group without photoactivation of RB (p<0.01). The data obtained indicate that under the influence of RB photoactivation, the aggregation activity of platelets changes, the severity and direction of the effect depend on the RB concentration. Change in functional activity of platelets is one of the manifestations of photodynamic modification of blood.