This study aimed to replicate a previous study which showed that endogenous opioid release, following an oral dose of amphetamine, can be detected in the living human brain using [11C]carfentanil positron emission tomography (PET) imaging. Nine healthy volunteers underwent two [11C]carfentanil PET scans, one before and one 3 h following oral amphetamine administration (0.5 mg/kg). Regional chan...

The narcoleptic syndrome is a life-long and sometimes familial disorder in which there is a disturbance of the rapid eye movement phase of sleep. Patients with periodic sleep in the daytime but no other symptoms seldom develop the narcoleptic syndrome and have a separate unrelated disorder. Twelve patients with the narcoleptic syndrome were treated separately with l(-) amphetamine and d(+) amph...

Amphetamines elevate extracellular dopamine, but the underlying mechanisms remain uncertain. Here we show in rodents that acute pharmacological inhibition of the vesicular monoamine transporter (VMAT) blocks amphetamine-induced locomotion and self-administration without impacting cocaine-induced behaviours. To study VMAT's role in mediating amphetamine action in dopamine neurons, we have used n...

Corticostriatal signaling participates in sensitized responses to drugs of abuse, where short-term increases in dopamine availability provoke persistent, yet reversible, changes in glutamate release. Prior studies in mice show that amphetamine withdrawal promotes a chronic presynaptic depression in glutamate release, whereas an amphetamine challenge reverses this depression by potentiating cort...

Stimulant sensitization is defined as an enhancement of the behavioral response to drug after repeated drug exposure. We have examined the relation between the expression of behavioral sensitization and the release of the striatal neurotransmitters acetylcholine (ACh) and dopamine (DA). Rats were treated with amphetamine (4 mg/kg i.p., b.i.d.) for 12 days. The behavioral response to amphetamine...

WBE was applied to evaluate illicit drug (i.e. amphetamine, cocaine, MDMA and methamphetamine), alcohol tobacco use in three Lithuanian cities 2018 2019. Considerable concentrations of methamphetamine were found the locations, suggesting a specific consumption pattern. Yet, unexpected high amphetamine (>4 ?g/L) detected two samples Kaunas 2018. Through chiral analysis non-target suspect precurs...

Repeated administration of amphetamine leads to enduring augmentation of its behavioral-activating effects, enhanced dopamine (DA) release in striatal regions, and morphological changes in DA target neurons. Here we show that exposure to a 2-week escalating-dose regimen of amphetamine prevents behavioral asymmetries of forelimb use and spontaneous (drug-independent) turning behavior following u...

Four injections (intraperitoneal) of 3 mg/kg amphetamine (2 hr apart) produced pronounced hyperthermia and sustained decreases in dopamine levels and tyrosine hydroxylase (TH) protein levels in the striatum of 15-month-old male rats. A partial recovery of striatal dopamine levels was observed at 4 months after amphetamine. In contrast, TH mRNA and TH protein levels in the midbrain were unaffect...

The amygdala is thought to mediate memory consolidation of amphetamine-induced conditioned place preference, a behavioral paradigm that requires memory for an association between environmental cues and the affective state produced by the drug treatment. Here we show that amphetamine induces long-term synaptic depression (LTD) in the amygdala. Amphetamine LTD is not affected by dopamine, seroton...