Effects of l-Dopa and l-3-Methoxytyrosine on d-Methamphetamine-Induced Motor Activity and Seizures Induced by Electroshock

Summary

l-3-Methoxytyrosine did not substitute for l-dopa, in increasing the threshold for electrically induced extensor seizures in mice, or in restoring the ability of d-methamphetamine to stimulate motor activity in rats treated with dl-α-methyltyrosine. At high doses l-3-methoxytyrosine inhibited the effect of l-dopa in both tests, l-3-Methoxytyrosine partially inhibited the increase in brain levels of dopa, dopamine, and norepinephrine produced by l-dopa. It is suggested that l-3-methoxy tyrosine may interfere with the uptake of l-dopa from the peritoneal cavity and from the blood into the brain.