CO2 EXCHANGE IN THE BLUE-CRAB, CALLINECTES-SAPIDUS (RATHBUN)

This study represents a first attempt to describe the pattern of carbon dioxide excretion in the gills of the blue crab, Callinectes sapidus. A computer simulation model was constructed, based on measurements of gill morphometry and blood carbon dioxide concentrations. Results of the simulation indicated that, although carbonic anhydrase is available in the gill epithelium for dehydration of HCO3−, it is probably not significantly involved in CO2 excretion. This conclusion was further supported by the observation that injection of a carbonic anhydrase inhibitor had no detectable effect on blood concentrations of CO2. Disequilibrium of the CO2‐HCO3− system is proposed as a significant factor in accounting for CO2 excretion. Copyright © 1979 Wiley‐Liss, Inc., A Wiley Company