previous studies have shown that ascorbic acid (aa) plays a crucial role in mammalian brain as avitamin and neuronal modulator. there is increasing evidence indicating that dopaminergic system and aacould affect learning and memory processes. in addition, vitamin c acts as a dopamine antagonist in thebrain. the aim of the present study was to evaluate the intra-hippocampal co-administration of ...

objective: curcumin is a major constituent of turmeric and influences many functions of the brain. in the present study, we investigated the effect of curcumin on yawning induced by apomorphine in rats. materials and methods: curcumin administered orallyfor 10 consecutive days. yawning was induced by subcutaneous (s.c.) injection of apomorphine (a dopamine receptor agonist) and the number of ya...

Agonist stimulated [S]guanosine 5¢-c-thiotriphosphate ([S]GTPcS) binding autoradiography was established for the examination of dopamine-D2 ⁄D3 receptors in human brain sections. The distribution of G proteins activated by dopamine-D2 ⁄D3 receptors was studied in whole hemisphere cryosections. Dopamine stimulated [S]GTPcS binding in brain regions with high densities of dopamine D2-like receptor...

Accumbal glycine modulates basal and ethanol-induced dopamine levels in the nucleus accumbens (nAc) as well as voluntary ethanol consumption. Also, systemic administration of the glycine transporter-1 inhibitor Org25935 elevates dopamine levels in nAc, prevents a further ethanol-induced dopamine elevation and robustly and dose-dependently decreases ethanol consumption in rats. Here we investiga...

The aim of the present study was to examine the effect of combined treatment of male Wistar rats with pramipexole and fluoxetine or sertraline in the forced swimming test. The obtained results showed that co-treatment with pramipexole (0.1 mg/kg) and fluoxetine (10 mg/kg) or sertraline (5 mg/kg) (in doses inactive per se) exhibited antidepressant-like activity in the forced swimming test. Sulpi...

Adenosine and dopamine are two important modulators of glutamatergic neurotransmission in the striatum. However, conflicting reports exist about the role of adenosine and adenosine receptors in the modulation of striatal dopamine release. It has been previously suggested that adenosine A(1) receptors localized in glutamatergic nerve terminals indirectly modulate dopamine release, by their abili...

The study was conducted to investigate the role for dopamine in the centrally mediated sympathoexcitatory response in rats with Type 2 diabetes (T2D). T2D was induced by a combination of high-fat diet (HFD) and low-dose streptozotocin (STZ). HFD/STZ treatment for 12-14 wk resulted in significant increase in the number of FosB-positive cells in the paraventricular nucleus (PVN) and rostral ventr...

Dopaminergic and glutamatergic neurotransmissions in the striatum play an essential role in motor- and reward-related behaviors. Dysfunction of these neurotransmitter systems has been found in Parkinson's disease, schizophrenia, and drug addiction. Cyclin-dependent kinase 5 (CDK5) negatively regulates postsynaptic signaling of dopamine in the striatum. This kinase also reduces the behavioral ef...

Elevated dopamine transmission in the nucleus accumbens is thought to be a primary mediator of addiction to cocaine. However, repeated exposure to cocaine is associated with the recruitment of glutamate transmission. This poses the possibility that the behaviors characterizing cocaine addiction, such as craving-induced relapse, may not be preferentially mediated by dopamine transmission. An ani...

Psilocybin, an indoleamine hallucinogen, produces a psychosis-like syndrome in humans that resembles first episodes of schizophrenia. In healthy human volunteers, the psychotomimetic effects of psilocybin were blocked dose-dependently by the serotonin-2A antagonist ketanserin or the atypical antipsychotic risperidone, but were increased by the dopamine antagonist and typical antipsychotic halop...