Peripheral nerve regeneration in primates during D-penicillamine-induced lathyrism

We have attempted to alter collagen metabolism in young squirrel monkeys by inducing lathyrism with D-penicillamine to weaken scar tissue. We then tested the effectiveness of this drug in improving regeneration of transected peripheral nerves at the wrists using a dose of 200 mg/kg/day. We did find a significant increase (doubling) in the soluble collagen in Ivalon sponge samples that had been implanted 3 weeks after the onset of drug treatment. We also compared the control and treated groups in terms of :(1) the rate of appearance of evoked muscle action potentials, (2) the amplitude of evoked muscle action potentials, and (3) the nerve conduction velocities. Using these tests we were not able to demonstrate any improvement in the quality or rate of nerve regeneration. The possible explanations for these observations are discussed.