Exposure to psychostimulants increases brain-derived neurotrophic factor (BDNF) mRNA and protein levels in the cerebral cortex and subcortical structures. Because BDNF is co-localized with dopamine and glutamate in afferents to the striatum of rats, it may be co-released with those neurotransmitters upon stimulation. Further, there may be an interaction between the intracellular signaling casca...

The abuse liability of the analgesic bicifadine was investigated in animal models used to predict the abuse potential of psychostimulants in humans. Bicifadine, cocaine, d-amphetamine, bupropion, and desipramine were evaluated for the production of cocaine-like discriminative stimulus effects in rats. Cocaine, d-amphetamine, and bupropion dose-dependently and fully substituted for cocaine. Bici...

Amphetamine and stress can sensitize mesolimbic dopamine-related systems. In Pavlovian autoshaping, repeated exposure to uncertainty of reward prediction can enhance motivated sign-tracking or attraction to a discrete reward-predicting cue (lever-conditioned stimulus; CS+), as well as produce cross-sensitization to amphetamine. However, it remains unknown how amphetamine sensitization or repeat...

Acute challenges with psychostimulants such as amphetamine affect impulsive behavior in both animals and humans. With regard to amphetamine, it is important to unravel how this drug affects impulsivity since it is not only a widely abused recreational drug but also regularly prescribed to ameliorate maladaptive impulsivity. Therefore, we studied the effects of amphetamine in two rat models of i...

Studies in rodents have shown that psychostimulant drugs such as cocaine and amphetamine cause endorphin release in the brain reward system. There is also evidence for the involvement of the opioid system in human psychostimulant dependence. The acute effects of an i.v. psychostimulant drug on the brain opioid system, however, have not yet been investigated in humans. We hypothesized that an i....

Pharmacological treatments are available for alcohol, nicotine, and opioid dependence, and several drugs for cannabis-related disorders are currently under investigation. On the other hand, psychostimulant abuse and dependence lacks pharmacological treatment. Mesolimbic dopaminergic neurons mediate the motivation to use drugs and drug-induced euphoria, and psychostimulants (cocaine, amphetamine...

BACKGROUND Two stimulant medications, modafinil and d-amphetamine, when tested individually, have shown safety and efficacy for treatment of cocaine addiction. We hypothesized that the combination of modafinil and d-amphetamine, at low doses, would show equivalent or greater benefit in reducing cocaine use compared to higher doses of each individual medication or placebo. METHODS Sixteen week...

The extent to which acute and repeated administration of the CB(1) agonist WIN 55,212-2 would affect the stimulatory properties of amphetamine was assessed in Lewis rats. In the first experiment, Lewis rats were treated with either 1 mg/kg of WIN 55,212-2 or vehicle and subsequently treated with 2 mg/kg amphetamine. Acute treatment with WIN 55,212-2 initially increased locomotor activity and th...

Opioids modulate brain dopaminergic function in various experimental paradigms. This study used the rotational model of behavior in rats with unilateral 6-hydroxydopamine-induced lesions of the nigrostriatal pathway to investigate this interaction. Doses of two presynaptically acting dopaminergic drugs, amphetamine and cocaine, were coadministered with several doses of the mu opioid agonist, mo...

Previously we reported that systemic administration of the dopamine D3 receptor-preferring partial agonist BP 897 blocked the expression, but not the acquisition, of amphetamine-conditioned activity. This suggested the hypothesis that BP 897 would block the expression, but not the acquisition, of amphetamine-conditioned place preference (CPP). Thus, during preconditioning rats had access to two...