Blockade of the central effects of d-amphetamine by amantadine. II.

1-Adamantanamine (amantadine) pretreatment significantly reduced the motor hyperactivity and hyperthermia caused by d-amphetamine in reserpinized mice. In drug-naive mice, when amantadine was administered after d-amphetamine, the motor activity caused by the latter also was decreased. Since our earlier studies showed that amantadine pretreatment also antagonized the increases in both motor activity and homovanillic acid (HVA) in the caudate nucleus caused by d-amphetamine in mice, it is suggested that the antagonism is due to a competitive blockade at the pre-synaptic level in the brain.