text: In view of the role of CA in acid-base balance as well as the fact that an increase or decrease in its activity is accompanied by an increase or decrease in intra- and extracellular pH, our results suggest that: firstly, << CA >> activation induced by [[ indomethacin ]] might cause changes in COX activity; secondly, PGs are synthetized as a consequence of the changes in COX activity, a hypothesis that requires further study.