Self-Administered Heroin and Cocaine Combinations in the Rat: Additive Reinforcing Effects—Supra-Additive Effects on Nucleus Accumbens Extracellular Dopamine

Synergistic elevations in nucleus accumbens extracellular dopamine concentrations during self-administration of cocaine/heroin combinations (Speedball) in rats.

The abuse of cocaine/opiate combinations (speedball) represents a growing trend in illicit drug use. Delineation of neurobiological substrates mediating the reinforcing effects of the combination may increase our knowledge of reinforcement mechanisms and provide useful new information for the development of pharmacotherapies. Several studies suggest dopaminergic innervations of the nucleus accu...

Cue-Induced Uncertainty and Prediction Error: Effects on Nucleus Accumbens Dopamine and Behavioral Responses to Self-Administered Cocaine and Saline

The acute effects of amphetamine derivatives on extracellular serotonin and dopamine levels in rat nucleus accumbens.

The acute effects of amphetamine derivatives on extracellular concentration of serotonin (5-HT) and dopamine in the nucleus accumbens were studied with in vivo microdialysis using conscious, freely moving rats. 5-HT, dopamine, and their major metabolites were measured by HPLC with electrochemical detection. Amphetamine (1.0-9.0 mg/kg) elevated dopamine levels considerably, but failed to affect ...

Effects of antipsychotic drugs on extracellular dopamine levels in rat medial prefrontal cortex and nucleus accumbens.

The present study was designed to compare the effects of typical and atypical antipsychotic drugs on extracellular dopamine (DA) levels in the medial prefrontal cortex (mPFC) and the nucleus accumbens (NAC), using in vivo microdialysis with dual probe implantation in awake, freely moving rats. Amperozide (2 and 10 mg/kg), clozapine (5 and 20 mg/kg), and olanzapine (10 mg/kg), all of which are a...

Effects of Dopamine Depletion in the Nucleus Accumbens on Lateral Hypothalamic Self - Stimulation in the Rat

Effects of Dopamine Depietion in the Nucleus Accumbens on Lateral Hypothalarnic Self-Stimulation in the Rat. Keiji Oda Considerable evidence implicates dopamine in brain stimulation reward. For example, dopamine antagonists or destruction of dopaminergic neurons reduce the reward effectiveness of medial forebrain bundle stimulation. Assessment of such effects is . complicated by across-subject ...