TOXIC NEUROFILAMENTOUS AXONOPATHIES AND FAST ANTEROGRADE AXONAL-TRANSPORT .4. INVITRO ANALYSIS OF TRANSPORT FOLLOWING ACRYLAMIDE AND 2,5-HEXANEDIONE

Recent investigations into the mechanisms of neurotoxicity of acrylamide and gamma-diketones have demonstrated reductions in the delivery of radiolabelled proteins to the distal axon. To differentiate a toxicant-induced compromise in the capacity of the fast anterograde axonal transport system from a neuron cell body processing effect, selective exposure of either the L5 dorsal root ganglion or sciatic nerve to 0.7 mM acrylamide (ACR) or 4 mM 2,5-hexanedione (2,5-HD) was performed during in vitro transport. Nerve exposure to ACR decreased the quantity of transport by 32%, 2,5-HD reduced the quantity by 44%. Ganglion exposure produced no significant changes. We conclude that both toxicants penetrate the nerve barriers and act directly and/or indirectly on the axonal transport mechanisms to cause the reductions in transport.