Effect of cycloheximide and d-amphetamine on brain catecholamines in two mouse strains.

The ability of cycloheximide to inhibit brain catecholamine synthesis in C57BL/6J and DBA/2J mice was studied to determine whether differences exist in these two strains with regard to this action and whether such effects correlate with previously reported differences in sensitivity to the amnesic effects. Administration of cycloheximide caused a dose-dependent inhibition of norepinephrine and dopamine synthesis in both strains. There was a significant effect due to strain on dopamine synthesis in drug-treated animals. d-Amphetamine partially prevented the decrease in the rate of synthesis of norepinephrine, dopamine and normetanephrine caused by cycloheximide in the C57 strain but enhanced the inhibition of synthesis of these compounds in the DBA strain. The results suggest that the reported differences in sensitivity to the behavioral effects of cycloheximide may be associated with the degree of inhibition of catecholamine synthesis in these two mouse strains.