Velyka A. Antioxidant and Functional Kidney State in Rats under Conditions of Water and Salt Loading and Experimental Nephropathy

The object of the research is kidneys and blood antioxidant protection system in rats and its functional status in case of water and salt loading in conditions of sublimate nephropathy. The goal of the research is to find out how the main indicators of pro-/antioxidant system and functional status of rats' kidneys will change during water and salt loading in normal conditions and in case of sublimate nephropathy. Methods used: biochemical, physiological; histological, histochemical and statistical. Novelty of the research: biochemical indicators that characterize the status of the pro-/antioxidant system and function of kidneys in rats in case of water and salt loading in conditions of sublimate nephropathy were researched. New characteristics of the process of free radical oxidation of lipids and proteins, of antioxidant system enzymes activity changes in the blood and kidneys of rats, of renal functional state changes and histochemical and histomorphological changes during the toxic affection with mercury (II) chloride in case of water and salt loading were revealed, based on the experimental data. Pathological changes that occur in kidneys as a result of oxidative stress progress in conditions of water and salt loading were studied and estimated; the state of macromolecules free radical oxidation and activity of organism antioxidant protection enzymes were studied in normal conditions and in case of water and salt loading. Results of the research: it was found out that during water and salt loading after modeled sublimate nephropathy noticeable oliguria occurs, that was characterized by decrease of urine output, increase of glomerular filtration rate (GFR), increase of creatinine and protein concentration in urea and also of sodium ions and their excretion; increase of titrated acids and ammonia excretion. It was found out that the solution of mercury (II) chloride (in the dose of 5mg/kg of the animal body weight) stimulates formation of products of free radical oxidation of molecules and activates the system of antioxidant protection in the blood of rats, regardless of the time of day. Structural and functional lesions, having occurred in case of introduction of mercury (II) chloride to animals result in classic necrotic nephrosis that is dependent on the daily periodicity with more severe course in rats at 8 PM in comparison with 8 AM. In these conditions introducing of water loading (5%) is accompanied with alterative process in which all of the epithelial cells are involved; and in case of salt loading (3%) it causes massive necrosis, especially in juxtaglomerular zone.