Choline acetyltransferase nerve identification method in early and late nerve repair.

Choline acetyltransferase (ChAC) measurement after complete transection of the sciatic nerve in rats revealed a steady increase in ChAC in the proximal nerve stump and a rapid drop in ChAC in the distal nerve stump. Ninety-six hours following transection no appreciable ChAC activity could be detected in the distal segment. The increase in the proximal segments was followed by a slight decline and leveling off at about twice the normal level. End-to-end nerve anastomosis, using the enzymatic nerve differentiation technique, could therefore be performed up to the first 96 hours. Nerve grafts could be used, with markedly improved results, up to the forty-fifth day following transection.