Human erythrocyte carbonic anhydrase B and C in chronic obstructive lung disease.

The levels of carbonic anhydrase B and C isozymes in human red cells were determined using a quantitative immunological technique in patients with chronic obstructive lung disease. A significant increase in the level of carbonic anhydrase B was observed in these patients, while the level of carbonic anhydrase C did not change substantially. Positive correlations were found between the level of carbonic anhydrase B and arterial CO2 tension and plasma HCO3 concentration. A negative correlation was observed between the levels of carbonic anhydrase B and blood pH. These findings suggest that the synthesis or degradation of carbonic anhydrase B isozyme is affected by arterial CO2 tension or plasma HC03 concentration. The clinical significance was also discussed in relation to these isozyme levels in red cell.