Influence of nerve cell body and neurolemma cell on local axonal protein synthesis following neurotomy

Abstract

The influence of the nerve cell body and neurolemma cell on selected aspects of local axonal protein synthesis as a consequence of neurotomy was studied in the hypoglossal nerve. The onset of the phase of rapid local protein synthesis in axons of the proximal stump, occurring 12–15 hr after transection, was not affected by decentralization at the time of neurotomy. This indicated that the perikaryon was not required to induce the rapid local synthesis response. Moreover, other experiments demonstrated that this response could be induced in intact nerve in regions subjected to gentle blunt dissection of the nerve away from surrounding tissue. Incorporation of [ 3H] leucine into axonal protein in proximal stumps, 18 hr after transection, occurred without apparent delay and proceeded at a linear rate through 2 hr in vitro. In addition, incubation in vitro with colchicine produced no significant effect on local synthesis of axonal protein. These findings were consistent with an intra-axonal site of protein synthesis and a local induction of the phase of rapid axonal protein synthesis.