Morphine withdrawal is characterized by functional alterations at the level of the
ventrotegmental area. We investigated the effects of chronic morphine administration and …

Daily administration of morphine in rats produces an increase in the motor stimulant effect of
subsequent morphine injections. This study was designed to characterize the behavioral …

The effects of morphine have been evaluated in two strains of mice showing different
behavioral responses. Morphine elicits an increase of locomotor activity only in the …

Repeated exposure to drugs of abuse causes persistent behavioural sensitization and
associated adaptations in striatal neurotransmission, which is thought to play an important …

Repeated treatment with psychostimulant drugs produces changes in brain and behaviour
that far outlast their initial neuropharmacological actions. The nature of persistent drug …

Numerous studies have demonstrated that genetic factors significantly influence opioid
ability to induce behavioral modification in mice. This differential sensitivity has been …

The nucleus accumbens is located ventromedially in the mammalian neostriatum. Nissl-and
myelin-stained material from the rat shows that the internal organization of the accumbens …

Following electrocoagulation of dopaminergic cell bodies of the mesolimbic system,[3 H]
naloxone binding decreases significantly in septum and nucleus accumbens. The latter …

Morphine is a highly potent analgesic with high addictive potential in specific contexts.
Although dopamine neurons of the ventral tegmental area (VTA) are widely believed to play …

The participation of amygdaloid and striatal structures in the various signs of morphine
withdrawal syndrome (MWS) has been investigated using two complementary approaches …