Post-amphetamine depression of self-stimulation behavior in rats: prophylactic effects of lithium

Rats reliably interrupted a photobeam for electrical brain stimulation when electrodes were situated in the substantia nigra. The reinforcing value of electrical brain stimulation diminished, markedly, when animals were exposed to long-term amphetamine treatment and then tested in the absence of the drug. Chronic lithium treatment administered in conjunction with amphetamine protected against the development of the post-amphetamine depression of self-stimulation responding. These findings were not related to drug-induced changes in locomotor activity.