[Efficiency and mechanisms of antihypoxic effect of ATP in newborn rats].

Effect of ATP (administered at the doses of 20 mg and 100 mg per kg of body mass) on sensitivity of 5-7 days old rats to acute hypoxia as well as content of 2,3-DPH and ATP in erythrocytes were studied. ATP exhibited the most effective antihypoxic influence at a dose of 100 mg/kg. After administration of ATP a dissimilar increase in content of 2,3-DPH and ATP was observed in erythrocytes of newborn rats maintained under conditions of normal atmospheric pressure. At the hypoxic step of compensated metabolic acidosis of blood the increase in content of 2,3-DPH, caused by the ATP administration, was combined with a less distinct alterations in acid-alkaline balance (SB, BE). Under conditions of decompensated metabolic acidosis preadministration of ATP did not prevent the pH dependent decrease in 2,3-DPH content in erythrocytes but slightly increased the ATP content. The alterations in content of 2,3-DPH and ATP, which occurred in erythrocytes apparently due to the effect of products of ATP dephosphorylation and which improved the oxygen transport by hemoglobin under conditions of oxygen deficiency, might be responsible for the positive influence of ATP on the stability of newborn rats to acute hypoxia.