Repeated treatment with psychostimulant drugs causes long-lasting behavioral sensitization and associated neuroadaptations. Although sensitization induced by a single psychostimulant exposure has also been reported, information on the behavioral and neurochemical consequences of a single psychostimulant exposure is sparse. Therefore, to evaluate whether behavioral sensitization evoked by single...

Antipsychotic sensitization and tolerance refer to the increased and decreased drug effects due to past drug use, respectively. Both effects reflect the long-term impacts of antipsychotic treatment on the brain and result from the brain's adaptive response to the foreign property of the drug. In this review, clinical evidence of the behavioral aspect of antipsychotic sensitization and tolerance...

Exposure to certain acute and chronic stressors results in an immediate behavioral and physiological response to the situation followed by a period of days when cross-sensitization to further novel stressors is observed. Cross-sensitization affects to different behavioral and physiological systems, more particularly to the hypothalamus-pituitary-adrenal (HPA) axis. It appears that the nature of...

Our studies examined the role of dopamine D4 receptors in the induction of behavioral sensitization to amphetamine (Amp) and accompanying neurochemical and molecular adaptive responses using a highly selective D4 antagonist, PNU-101387G. Behavioral sensitization to an acute challenge of Amp (2 mg/kg, s.c.) was observed in rats pretreated with five daily doses of Amp (2 mg/kg/d, s.c.) followed b...

Rats were pretreated with daily cocaine or saline injections for 1 week. The rats treated with daily cocaine were separated into two groups: a sensitized group of animals demonstrating > 20% increase in motor activity on the last injection compared with the first injection of daily cocaine, and a nonsensitized group showing < 20% elevation. At 2-3 weeks after the last daily injection, four expe...

AIM To investigate effects of thenorphine, a new compound of partial agonist of mu-opioid receptor, on the locomotor activity and the behavioral sensitization to morphine in mice. METHODS Locomotor activity was observed after administration of thenorphine or co-administration of thenorphine and morphine in mice. Mice were induced behavioral sensitization to morphine by intraperitoneal injecti...

In recent years, abuse of amphetamine-type stimulants (ATS) has become a severe problem to the whole world, and methamphetamine (METH) has accounted for the majority percent of global ATS seizures. It has been confirmed that the changes of histone acetylation involve in the regulation of METH addiction [1]; however, the effects of METH on histone deacetylase (HDAC) are poorly understood. Behavi...

Previous work established that repeated olanzapine (OLZ) administration in normal adolescent rats induces a sensitization effect (i.e. increased behavioral responsiveness to drug re-exposure) in the conditioned avoidance response (CAR) model. However, it is unclear whether the same phenomenon can be detected in animal models of schizophrenia. The present study explored the generalizability of O...

Drosophila melanogaster can be used to identify genes with novel functional roles in neuronal plasticity induced by repeated consumption of addictive drugs. Behavioral sensitization is a relatively simple behavioral output of plastic changes that occur in the brain after repeated exposures to drugs of abuse. The development of screening procedures for genes that control behavioral sensitization...

The nucleus accumbens (NAc) has been shown to play a key role in the brain's response to methylphenidate (MPD). The present study focuses on neuronal recording from this structure. The study postulates that repetitive exposure to the same dose of MPD will elicit in some rats behavioral sensitization and in others tolerance. Furthermore, the study postulates that NAc neuronal activity recorded f...