Effects of dopamine and amphetamine on mouse caudate neurons recorded in vitro.

Mouse caudate neurons recorded from brain slices in vitro displayed one of three different types of electrophysiological activity. These were: (a) a regular, pacemaker-like firing pattern; (b) an irregular discharge pattern, and (c) a bursting pattern. Both dopamine and D-amphetamine produced a dose-dependent increase in the activity of the regularly and irregularly firing caudate neurons when placed in the incubation bath, but had no effect on the bursting neurons. These studies demonstrate that the excitatory effect of amphetamine on caudate neurons is due to a direct action on these cells.