Possible Interaction: Amphetamine and Dopamine Antagonists

“Multiple daily amphetamine injections in rats decreased both [3H]agonist as well as [3H]antagonist striatal dopamine receptor binding.”

“Apomorphine (2 mg/kg), amphetamine (10 mg/kg), methylphenidate (30 mg/kg) and piribedil (12 mg/kg) induced stereotypy which could be blocked by dopamine receptor blockers haloperidol (1 mg/kg) or pimozide (1 mg/kg) but yohimbine (2 mg/kg) an alpha adrenoceptor blocker was ineffective.”

“We conclude that the primary effect of a dopamine D2/D3 receptor antagonist is a potentiation of the effect of amphetamine on extracellular striatal dopamine levels, which may contribute to the enhanced stereotypic effects observed when paired with amphetamine.”

“Systemic administration of d‐amphetamine (1.5, 6 mg/kg) or cocaine (10, 20 mg/kg) increased locomotor activity, which at low doses was blocked by pretreatment with the dopamine D1 receptor antagonist SCH 23390 (1 mg/ kg).”

“… dopamine D1 antagonist , SCH 23390 (0.01, 0.1, 1.0, 2.0 mg/kg) or the …/kg), to block the establishment of place conditioning with either the nonselective dopamine agonist, amphetamine (2.0 mg/kg), the D1 agonist, SKF 38393 (… (1.0 mg/kg), was evaluated in rats.”

“In separate groups of pretrained animals, both dopamine antagonists (haloperidol, alpha-flupenthixol) and agonists (apomorphine, metamphetamine ) blocked performance on both place and cue tasks, although there were individual differences in sensitivity of the rats.”