Carbonic anhydrase activity of human peripheral nerves: a possible histochemical aid to nerve repair

The return of usable function after injury of peripheral nerves depends upon the appropriate regeneration of axons to their end organs. Debridement trimmings of severed nerves harvested during surgery were stained to demonstrate carbonic anhydrase activity. This histochemical method can be accomplished within 3 to 4 hours of receiving the tissue. Nerve fascicles were readily discriminated from one another by the individual staining patterns of their constituent axons. Axoplasmic staining was predominantly a feature of sensory fibers, and myelin staining was characteristic of skeletal motor axons. Carbonic anhydrase histochemistry may provide a means of accurately matching fascicles in cut nerve ends.