Recent work implicates regulation of neurogenesis as a form of plasticity in the adult rat
hippocampus. Given the known effects of opiates such as morphine and heroin on hippocampal …

Cocaine addiction is thought to involve persistent neurobiological changes that facilitate
relapse to drug use despite efforts to abstain. But the propensity for relapse may be reduced by …

Chronic exposure to drugs of abuse is known to modulate tyrosine hydroxylase (TH) levels
in the mesolimbic dopamine system. In this study, 12 d of cocaine self-administration in rats (…

The specific opioid receptor antagonist naloxone modifies the effects of amphetamine in a
wide variety of behavioral paradigms. Naloxone also attenuates the amphetamine-induced …

In this study we examined the effect of 2‐(phosphonomethyl)pentanedioic acid (2‐PMPA)
and GPI 5693, selective inhibitors of the enzyme N‐Acetylated‐α‐Linked‐Acidic Dipeptidase (…

Opioid antagonists attenuate behavioral effects of amphetamine and amphetamine-induced
increases in extracellular dopamine levels in nucleus accumbens and striatum of rats but do …

The specific opioid receptor antagonist naloxone attenuates the behavioral and neurochemical
effects of amphetamine. Furthermore, the amphetamine‐induced increase in locomotor …

Previous studies on rats have shown that the opioid antagonist naloxone attenuates
amphetamine-induced stimulation of locomotor activity and increases in extracellular dopamine in …

Dopamine is the main catecholamine implicated in the reinforcing effects of abused drugs
such as the psychomotor stimulants cocaine and amphetamine and the opioids including …

NATURE| VOL 421| 2 JANUARY 2003| www. nature. com/nature 70 reward1. Here we show
that extinction training during withdrawal from chronic cocaine self-administration induces …