Dynamics of changes in blood parameters against the background of the use of a bacteriochlorin series photosensitizer in rats in an experiment

Photodynamic therapy (PDT) is a method of treating tumor and inflammatory processes using an active substance, a photosensitizer (PS), and a light component (usually laser radiation), which affects the PS when it enters pathological cells. An urgent task of modern photodynamic therapy is the development of new effective photosensitizers that are activated in the long-wave part of the spectrum, which allows for deeper and more effective tumor irradiation one of this is PS «bacteriochlorin». Preclinical study of the effect of a new bacteriochlorin photosensitizer on blood parameters to confirm the safety of this substance is an important aspect when introducing it for both veterinary and medical purposes. This is due to the fact that animal studies are experimental models of human diseases due to the similarity of biology and morphology of some tumors. In this work were used different doses of bacteriochlorin: 1.0, 2.0, 3.0 and 5.0 mg/kg. Before beginning of experiment was carried out control measurement of hematological and biochemical parameters of blood. The photosensitizer was made at intervals of 14 days. Based on the results of the experiment, we recommend a therapeutic dose of the photosensitizer 1 mg/kg. Bacteriochlorin in doses up to 2 mg/kg does not affect blood parameters and the general condition of animals. The photosensitizer "bacteriochlorin" in therapeutic and slightly exceeding doses slightly changes the functioning of the renal and hepatobiliary systems. The general clinical blood test for all administered doses of the drug was maintained at the level of reference values, and differed significantly in relation to the control group only when the dosage was increased by 5 times. The use of photosensitizer "bacteriochlorin" in acceptable doses cannot cause deterioration in the animal's condition.

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