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This publication presents the results of research that was aimed at elaboration of adaptive potential reducing model, intended for toxicological experiments. Two series of research (with a duration of 70 days each) were conducted on Wistar rats. In the 1st series five groups of animals received diets with 100, 75,50,25 and 0% of vitamins B1, B2, B3, B6 and minerals(Fe3+ and Mg2+); in the 2nd series four groups of animals received diets with 21.37, 9.94, 4.62, 2.15% of this vitamins and minerals. In the 1st series of studies the intervals of maximum, medium and minimum content of essential nutrients in the diet was established; in the 2nd series the range of the lowest possible concentrations of these elements that provided the lowest level of adaptive potential and not causing the pathology development was determined. The certain set of hematological, biochemical, immunological and other indicators were investigated, this article analyzes the results of zoometric studies, mortality of animals, as well as the results of antioxidant status (activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and malondialdehyde content in red blood cells) studies. Based on the evaluation of the data which were obtained in the 1st series, it follows that a dose reduction of relevant essential nutrients to 25% didn't significantly affect the values of the studied indicators, and the complete elimination of these substances resulted in massive death of animals. In the 2nd series a significant differences between the groups were observed from the range of increased mortality (groups with 2.15 and 4.62% content of essential nutrients) to the range of deviations from central tendency of some parameters (group with 21.37% content). The data allowed to trace the dependence of these differences on the levels of vitamins and minerals in the diet. The results were used to determine threshold values of vitamins and minerals that provided the necessary reduction of the adaptive potential level in male and female rats. Taking into account the risk of pathology development, three dosages of essential substances have been established - optimal, marginal and submarginal, which provide consistent decline of adaptive potential of laboratory animals: 75, 30 and 19% for males and 75, 28 and 18% for females, respectively. The modification of vitamin and mineral composition of the diet can be used as a model of adaptive potential reduce in toxicological research. |
