Sarcolemmal (SL) carbonic anhydrases in mouse skeletal muscle.

The activities are given in enzyme units per protein concentration in the sarcolemmal membrane fraction. They are derived from activity measurements in WT, CA IV- and CA IV-CA XIV-double-ko mouse muscle [6]. The immunoctyochemical results presented here allow us to attribute CA IV and CA XIV to the surface membrane alone and CA IX exclusively to the T tubules.*CA IV is localized on the entire surface membrane, but greatly enriched at the openings of T tubules,**CA XIV is homogeneously distributed over the entire surface membrane.