Influence of photoactivated coproporphirin on microcirculation

Abstract

The aim –to investigate the effect of photoactivated coproporphyrin III (KP III) on microcirculation in the rat mesenteric vascular bed. Material and methods. The study was performed on 20 male rats, divided into 4 groups: 1) control; 2) KP III; 3) laser irradiation; 4) laser irradiation on combined with prior administration of the KP III.The objectof the study was venules (20–40 µm) of the mesentery of the small intestine. The study of blood flow velocity in the venules was performed using the method of intravital biomicroscopy. The velocity parameters were registered using a high-speed video camera Basler acA2000 (Germany). Coproporphyrin III (Elast, Russia) at a dose of 10 mg/kg was injected into the tail vein 3 hours before laser irradiation. Irradiation was performed using a Lakhta Milon semiconductor laser apparatus (Qualitek, Russia) (λ=635 nm, 0.1 W/cm2 ; 300 s; 30 J/cm2 ).Results.Administration of KP III without subsequent irradiation did not affect the blood flow velocity during the entire observation period. Laser irradiation of venules without prior administration of KP III led to an increase in blood flow velocity by 39.1 % (p<0.05). After laser irradiation and administration of KPIII, there was a gradual decrease in flow velocity after the photoactivation process.Conclusions. We studied the effect of photoactivated KP III on microcirculation in the mesentery of the small intestine of rats. Changes in the blood flow velocity in the venules of the mesentery affected by KP III and laser irradiation develop mainly in the post-radiation period and could be associated with endothelial dysfunction.