ОСОБЕННОСТИ ВОЗДЕЙСТВИЯ ДЕЦИМЕТРОВЫХ ЭЛЕКТРОМАГНИТНЫХ ВОЛН НА АКТИВНОСТЬ ПИРУВАТКИНАЗЫ МОЗГА КРЫС В ОНТОГЕНЕЗЕ

Abstract

The effect of decimetric microwaves (DMW) on the activity of pyruvate kinase (PK), one of the energy supply enzymes, was investigated in the brain structures of 3-, 6-, and 24-month-old white non-linear rats. Experimental rats were exposed on a daily basis for 20 min to 10 and 30 μW/cm² of DMW irradiation over a period of 10 days. It was established that PK activity in the cortical and subcortical brain structures, which differ in their oxygen supply, morphofunctional and phylogenetic characteristics, reacts differently to the effect of DMW: at 10 μW/cm² it increases while at 30 μW/cm² it decreases. In mitochondrial subcellular fractions of the brain structures, PK activity was lower at 10 μW/cm² than at 30 μW/cm². In cytosolic subcellular fractions, no significant differences were revealed in PK activity at different intensities of DMW irradiation, while these indicators, taken separately, were significantly different compared to the control (p < 0.01; p < 0.001). There are two alternative assumptions to account for the obtained results. The increased PK activity in the brain structures studied may reflect a metabolic adaptation aimed at protecting the structural integrity and functional components of nerve cells from detrimental effects of DMW irradiation. Conversely, a lack of energy due to a drop in PK activity, in turn, causes various negative secondary metabolic changes and free-radical oxidation in nerve cells. Our data indicate that both at 10 and 30 μW/cm² of DMW irradiation, endogenous signals in the rat brain are directed from cortical to subcortical structures, but PK activity does not recover to the control values. It is hypothesized that under the effect of DMW, the cerebellum, orbital and sensorimotor cortices serve as donors, while the limbic cortex and hypothalamus are acceptors in the system of signal transduction.