Management of the Acid-Base Balance by the Red Blood Cell Carbonic Anhydrase (RCA). I. Correlation of the RCA Activity and Acid-Base Balance in the in Vitro and in Vivo Experiments

Abstract

Taki, K., Takamura, M., Sotani, H. and Wakusawa, R. Management of the Acid-Base Balance by the Red Blood Cell Carbonic Anhydrase (RCA). I. Correlation of the RCA Activity and Acid-Base Balance in the in Vitro and in Vivo Experiments. Tohoku J. exp. Med., 1983, 139 (4) 339-348 - Changes in RCA activity are known to affect the acid-base balance, but a clear relationship between RCA activity and acid-base balance has not yet been established. The relationship between RCA activity and acid-base balance was studied in tonometry with 4 mixed gases for 6-9hr, in healthy adults at rest, in halothane anesthesia and in hypothermia. RCA activity increases when pH and HCO₃-/P_CO2 ratio increase and P_CO2 decreases in vitro. It also increases when pH and HCO₃-/P_CO2 ratio decrease and the range of P_CO2 broadens in vivo. The relationship between RCA activity and the HCO₃^-/P_CO2 ratio is a fan shape, because a change of the HCO₃^-/ P_CO2 ratio precedes the change of RCA activity. Some factor which increases the RCA activity may be produced secondarily in the body under the influence of high P_CO2. Probably the acid-base balance is corrected by reduction of the RCA activity in the case of alkalosis, and the acid-base balance may be corrected by an increase in RCA activity in the case of acidosis