Inhibition of dopamine receptors by endogenous amines: binding to striatal receptors and pharmacological effects on locomotor activity

Endogenous amine 1-benzyl-1,2,3,4-tetrahydroisoquinoline (1BnTIQ) derivatives are synthesized, and their activity for dopaminergic systems are evaluated in vitro and in vivo by receptor binding assay and pharmacological tests. It is proposed that 1BnTIQ derivatives can act as endogenous dopaminergic antagonists.