Simulation of photodynamically-induced thrombosis of the femoral vein of rats

Abstract

The purpose of the work is to determine the conditions that ensure the formation of a stable thrombus in the femoral vein of rats with photodynamic damage.Material and methods. The experiments were carried out on male Wistar rats weighing 250–270 g. A photosensitizer (FS) Bengal rose (ACROS ORGANICS, USA) (BR) was administered intravenously at a dose of 17 mg/kg and after 60 minutes a vascular clamp was applied to the femoral vein. Distal to clamping, a 30-minute laser irradiation of a vein was performed (DPSS diode laser, Republic of South Korea, 532 nm, 60 mW, irradiation area – 1 mm2 ). The clamp was removed after 90 min after cessation of irradiation. The blood flow was recorded by the method of high-frequency Doppler ultrasound (MinimaxDoppler-K Russia). Cessation of blood flow was considered as an indicator of occlusion of femoral vein.Results. Rats, after the clamp was removed, had no blood flow in the irradiated veins, and after 24 hours it was not restored. Histology revealed severe damage of all layers of the vascular wall and the formation of a blood clot filling the lumen of the vessel. After a 30-minute irradiation without clamping the vein, the blood flow was maintained, although damage to the vascular wall was detected. Introduction of BR and clipping of the vessel without irradiation caused minimal damage to the vascular wall and did not lead to thrombosis.