[The effect of sodium alpha-glutarate on enzymatic transamination activity and on succinate dehydrogenase in rats with different resistances to hypoxia].

It have been found that intraperitoneal alpha-ketoglutarate injection (20 mg/100 g body weight) results in increase in the influence of cholinergic regulation mechanisms. It also results in increase of aminotransferase activity on background of the decrease of succinate dehydrogenase activity in liver and pancreas tissues and in small intestines mucous. Activity of transamination enzymes and succinate dehydrogenase activity is much higher in the case of rats with high hypoxia resistance, alpha-ketoglutarate injection results in increase of transamination enzymes activity in the organisms of rats with low resistance to hypoxia up to the control level of rats with high resistance, and simultaneously increases rats resistance to hypoxia.

[The effect of the parenteral administration of alpha-ketoglutarate on the resistance of rats to ionizing radiation and on their cholinergic systems].

We have investigate the effect of sodium ketoglutarate intraperitoneal injection (20 mg/100 g body weight) made 0.5 hour before and 1, 2 and 3 hours after total X-ray treatment (259 mKl/kg) on the survival of rats. Simultaneously we have define changes in cholinesterase-acetylcholine system and content of adrenaline and noradrenaline in liver and pancreas tissues, small intestines mucous and in blood.

[Role of calcium ions in the mechanism of action of acetylcholine on energy metabolism in rat liver mitochondria].

It is shown that administration of acetylcholine to animals (50 micrograms per 100 g of body weight) leads to the activation of respiration and oxidative phosphorylation in the rat liver mitochondria under oxidation of alpha-ketoglutarate; this effect depends on the concentration of calcium ions in the incubation medium of mitochondria. The rate of ADP-stimulated respiration of mitochondria of experimental animals reaches its maximum level under lower concentrations of Ca2+ than in the control animals. The results of investigation of dependence of acetyl choline effect on respiration of mitochondria on the concentration of alpha-ketoglutarate in calcium and calcium-free incubation medium have shown that the half-maximum effect of acetylcholine is observed in calcium medium at lower concentration of the substrate than in calcium-free medium.

[Adrenergic and cholinergic regulation of respiratory efficiency of secretory cells].

The influence of sympathetic and parasympathetic systems on the secretory cell respiration is mediated at the subcellular level by adreno- and cholinoreceptors of plasmatic membranes and is related to selective oxidation of two different substrates of the Krebs cycle: succinate and alpha-ketoglutarate, both being involved into two reciprocal mediator-hormonal-substrate-nucleotide systems: catecholamines-succinate-cAMP-ATP and acetylcholint-alpha-ketoglutarate-cGMP-GTP. The reciprocation of these systems is necessary for regulation of cell oxygen demand and effective oxygen utilization for ATP-synthesis and synthesis of other macroergical compounds depending on the functional state of a cell.

[Mechanism of reciprocal effects of acetylcholine on oxidation of alpha-ketoglutarate and succinate in heart and liver mitochondria. Factors influencing detection of the acetylcholine effect].

Effect of acetylcholine administration (50 mg/100 g) on phosphorylating oxidation in the liver and heart mitochondria of rats and guinea pigs has been studied. The reciprocal effect of acetylcholine on alpha-ketoglutarate and succinate oxidation (acceleration and inhibition, respectively) was observed. In both cases, the ADP/O coefficient increased.