[Structural and functional changes in rat liver mitochondria under calcium ion loading in the absence and presence of flavonoids].

The aim of the present work was to elucidate the mechanisms of calcium ion-induced impairments of the ultrastructure and functional activity of isolated rat liver mitochondria in the absence and presence of a number of flavonoids in vitro. In the presence of exogenous Ca²⁺ (20-60 μM), mitochondrial heterogeneity in size and electron density markedly increased: most organelles demonstrated a swollen electron-light matrix, bigger size, elongated cristae and a reduced their number, a damaged native structure of the inner membrane up to its detachment, and some mitochondria showed a more electron-dense matrix (condensed mitochondria). The calcium-induced opening of the mitochondrial permeability transition pores (MPTP) resulted in the ultrastructural disturbances and in the effective inhibition of the respiratory activity of rat liver mitochondria.

[Taurine induces an imbalance in the pool of neuroactive amino acids and biogenic amines in regions of the brain].

The paper deals with the consequences of exogenous taurine (Tau) administration (650 mg/kg, i.p., singly, for 30 min) and possible mechanisms of this compound participation in the formation of the structure of the neuroactive amino acid pool, biogenic amines and their metabolites in the hypothalamus (H), basal ganglia (BG) and cerebellum (C) of the brain of male rats weighing 160-280 g.

[The amino acid pool of the liver during activation of glutathione synthesis].

Regularities of formation of a pool of free amino acids and their derivatives in the liver of rats were studied during L-2-oxothiazoidin-4-carboxylate-induced glutathione synthesis activation. It was shown that an increase in concentrations of sulfur-containing (cysteate, cysteine) and branched-chain (valine, isoleucine, leucine) amino acids was the most typical change. The correlation and linear-discriminant analysis of the whole range of the compounds studied in the dynamics of the experimental process has proved high informativeness of glycogenic amino acid levels, activation of the whole chain of synthesis and degradation of thiol-containing amino acids as well as determination of the obtained shifts in concentrations of reduced glutathione.