Disregulatory shifts in the red blood system during prolonged intoxication with copperzinc-pyrite ore (experimental study)

Abstract
Introduction. Heavy metal compounds of copper-zinc pyrite ores can negatively affect the blood-forming and composition of peripheral blood of workers at mining and milling industry. Studying of the mechanisms of the development of metal-induced anemia will help in the search of ways to correct disorders in the red blood system. The study aims to estimate the mechanism of functional disorders of the central and peripheral parts of erythron in the long-term intoxication of natural heavy metal compounds in the experiment. Material and methods. The work was carried out on 50 white non-linear male rats weighing 220,5±15,5 g. Sample of the studied ore was provided by Uchalinsky Mining and Refining Plant (Uchaly, Bashkortostan Republic, Russia). The rats were given a water suspension of copper-zinc powder daily for 90 days for 1 hour before feeding, the dose was calculated on the basis of the maximum allowable concentration of lead (0,2-0,5 mg/kg) and cadmium (0,02-0,1 mg/kg) in grain and bread. The number of red blood cells, reticulocytes, hemoglobin and the concentration of erythropoietin were determined in the peripheral blood. Bone marrow erythropoiesis was evaluated by the quantitative and qualitative composition of erythroblastic islets (EI) and indicators of proliferation and maturation of erythroblasts in the EI. Statistical analysis was conducted using Mann-Whitney's non-parametric methods and Pearson's paired correlation. Results. On the 10th day young EI completely disappeared in the bone marrow, and erythropoiesis was supported only by reconstruction. In the peripheral blood the number of erythropoietin decreased by 22%, the number of reticulocytes doubled. The number of mature EI in the bone marrow was doubled by 30 days. By 90 days the number of reticulocytes in the blood returned to normal, but in the bone marrow the content of young forms of EI was 5 times less than the control values. Correlational analysis showed the absence of direct links between the central and peripheral parts of erythron in animals with chronic intoxication of copper-zinc pyrite ore, that present in the control group. Conclusion. With long-term combined exposure with heavy metals of natural origin, regulatory processes in the red blood system are disrupted, that is accompanied with inhibition of erythropoiesis in the EI.