[Role of CO2 fixation in increasing the body's resistance to acute hypoxia]

In rats, the phenomenon of considerable increase in resistance to acute hypoxia observed after 2-hour stay under conditions of gradually increasing concentration of CO2, decreasing concentration of O2, ANd external cooling at 2--3 degrees seems to be based mainly on changes in concentration of CO2 (ACCORDINGLY, PCO2 and other forms of CO2 in the blood). The high resistance to acute hypoxia develops as well after subcutaneous or i.v. administration of 1.0 ml of water solution (169.2 mg/200 g) NaHCO2, (NH4)2SO4, MgSO4, MnSO4, and ZnSO4 (in proportion: 35 : 5 : 2 : 0.15 : 0.15, resp.) or after 1-hour effect of increased hypercapnia and hypoxia without cooling.