Деякі показники перекисного окиснення ліпідів та глутатіонової системи у кішок за хронічної патології нирок

Abstract

У статті розглядаються зміни окремих біохімічних показників крові за хронічної патології нирок у кішок, зокрема інтенсивність перекисного окиснення ліпідів та концентрація глутатіону у крові. Встановлено, що у кішок з ХПН збільшується вміст загального білка, неорганічного фосфору, сечовини, креатиніну, зменшується концентрація кальцію, збільшується концентрація продуктів ПОЛ: гідроперекисів ліпідів, тоді як концентрація відновленого глутатіону суттєво зменшується.

One of the most spread non-infectious diseases in cats is a group of kidneys’ pathologies, in animals of elder age group kidneys’ chronic pathologies amount to 30%. The purpose of this research was to study the processes of lipids’ peroxidation (LP), which are the starting ones in the development of inflammatory processes and of glutathione, that is the main substrate of an antioxidant system. It is known that LP results in the integrity damage of fatty acids of cell membranes, of some proteins, that in its turn causes disintegrative processes in enzymes composition, as well as deterioration of filtration and reabsorption processes in kidneys. The research was conducted on 5-8 years old cats, which had kidneys’ chronic pathologies. The haematologic and biochemical analysis of animals’ blood showed that in cats with kidneys’ chronic pathology was observed the decrease in hemoglobin concentration, red blood cells amount, and the increase in hematocrit, - the latter is the sign of dehydration processes. The increase in the total amount of white blood cells and neutrophils, and the decrease in the amount of lymphocytes were revealed in white blood indices of sick animals. Kidneys’ chronic pathology causes some changes in the biochemical composition of cats’ blood: it has been established that the content of crude protein of blood serum increases, that is one more indicator of dehydration. In addition to that, the concentration of urea and creatinine which are the indicators of kidneys’ functional state increases as well. A decreased kidneys’ function results in the increase in Calcium excretion as well as in phosphate retention in blood, which affects the acid-base balance. The study of the biochemical phenomena which are the basis for kidneys’ chronic pathology, is of great importance for studying the pathologic process. The lipids’ peroxidation occurs as a result of an increase in reactive oxygen species, it also results in metabolites accumulation which change both the construction and the functions of cell’s structural elements. The cats of an experimental group had a little increase in the concentration of lipids’ hydroperoxides, as well as more than 71% increase in final LP product amount – malon-dialdehyde. An inequal increase in the amount of two LP products was probably caused by a fast hydroperoxides disassimilation and by the accumulation of a final product – malon- dialdehyde. An inactivation of LP products is implemented by an antioxidant system. One of the most important substrate of an antioxidant system is glutathione. A renewed glutathione takes part not only in the processes of antioxidant protection but also in proteins renewal which contain sulphydryl groups and take part in oxide renewal processes in kidneys. A content of a renewed glutathione fraction in blood of cats with kidneys’ pathologies decreased as compared to control by 10.5%. Thus, chronic kidneys’ pathology in cats results in the intensification of the processes of lipids’ peroxidation and the accumulation of lipids’ hydroperoxides and malon-dialdehyde in blood. At the same time the fraction of a renewed glutathione decreases. Such changes result in the deterioration of the kidneys’ functional capability, urea, creatinine and non-organic phosphorus retention, as well as in the increase in Calcium excretion.