Single doses of acrylamide reduce retrograde transport velocity

Single doses of acrylamide (0-1.3 mmol/kg) produced a dose-dependent decrease in the transport of 125I-tetanus toxin to the perikarya of sensory neurons in dorsal root ganglia and motor neurons in ventral spinal cord. Acrylamide was a more potent inhibitor of retrograde transport in sensory axons than in motor axons. Substantially greater doses of N,N'-methylene-bis-acrylamide, a reportedly non-neurotoxic analog of acrylamide, were required to alter the axonal transport of 125I-tetanus toxin. Velocity of retrograde transport was assessed by determining the position of the leading edge of transported 125I-tetanus toxin at times following single doses of acrylamide. Acrylamide reduced the velocity of 125I-tetanus toxin transport in a dose-dependent manner by up to 75%. No change in neuronal uptake of 125I-tetanus toxin was detected. It is concluded that single doses of acrylamide produce profound alterations in retrograde transport which precede the appearance of structural changes in affected nerve fibers.