text: Doses of dimethocaine (1.7 mg/kg) and cocaine (0.3 mg/kg) which produced full (> 80%) substitution for cocaine were administered in combination with the << dopamine D1 receptor >> antagonist SCH 39166 ([[ (-)-trans-6,7,7a,8,9,13b-hexahydro-3-chloro-2-hydroxy-N-methyl-5H -benzo [d]naphtho-(2,1-b)azepine ]]) and the dopamine D2 receptor antagonist raclopride (both at 0.003-0.03 mg/kg).