LEAD AND CADMIUM SUBCHRONIC INTOXICATION IN RATS AS A FACTOR OF DAMAGE TO THE CARDIOVASCULAR SYSTEM

Lead-cadmium intoxication is an occupational risk factor for copper-smelting industry workers. People inhabiting the areas near the copper plants are also at risk. Subchronic intoxication was modeled by repeated intraperitoneal injections of lead acetate and cadmium chloride both in isolation and in combination, 3 times a week for 6 weeks. A heart rate decrease in animals with Cd intoxication and a blood flow velocity decrease in those with Pb intoxication have been found. The impact of Pb and Cd on blood pressure proved to be contra-directional. ECG analysis revealed a prolonged duration of QRS in Cd intoxication, a prolonged QT interval and a baseline lowering in Pb+Cd intoxication. A variety of changes has been found with respect to the diameter of cardiomyocytes and the thickness of aortic wall layers in Pb and/or Cd intoxication. Any toxic exposure resulted in the decrease in number of nuclei per unit area of myocardium histological preparation.

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