Background and Objective: Methylphenidate (MPH), as a central nervous system stimulant, is often used to manage hyperactive disorders. The literature is scarce regarding the behavioral consequences of chronic MPH treatment and the role of involved receptors. Thus, in the current study involved receptors in MPH induced-anxiety, depression and motor activity disorders were evaluated. Materials a...

Although D2 dopamine receptors have been localized to olfactory receptor neurons (ORNs) and dopamine has been shown to modulate voltage-gated ion channels in ORNs, dopaminergic modulation of either odor responses or excitability in mammalian ORNs has not previously been demonstrated. We found that <50 microM dopamine reversibly suppresses odor-induced Ca2+ transients in ORNs. Confocal laser ima...

Several dopamine agonists, administered i.m., produced persistent, excessive and non-localized scratching in squirrel monkeys (Saimiri sciureus). Studies were conducted with a series of drugs to determine the pharmacological mechanisms responsible for this effect. All of the dopamine D2 agonists studied produced dose-related increases in scratching, whereas several dopamine D1 receptor agonists...

The benzamide derivative amisulpride shows a unique therapeutic profile being antipsychotic, at high doses, and disinhibitory, at low doses, while giving rise to only a low incidence of extrapyramidal side effects. In vitro, amisulpride has high affinity and selectivity for the human dopamine D2 (Ki = 2.8 nM) and D3 (Ki = 3.2 nM) receptors. Amisulpride shows antagonist properties toward D3 and ...

Dopamine, cis-flupenthixol, and dibutyryl cAMP affected the standing potential and light-evoked responses of the perfused cat eye in vitro. At micromolar concentrations, dopamine, a retinal neurotransmitter, increased the standing potential of the eye. At slightly higher concentrations, dopamine abolished the "light peak," a slow voltage response to light generated by the retinal pigment epithe...

BACKGROUND AND PURPOSE Systemic administration of N,N'-dodecane-1,12-diyl-bis-3-picolinium dibromide (bPiDDB), an antagonist of nicotinic acetylcholine receptors (nAChRs) attenuated the nicotine-induced increase in dopamine levels in nucleus accumbens (NAcc). EXPERIMENTAL APPROACH Using in vivo microdialysis, we investigated the effects of local perfusion of the novel nAChR antagonist bPiDDB ...

BACKGROUND The trafficking of mitochondria within neurons is a highly regulated process. In an earlier study, we found that serotonin (5-HT), acting through the 5-HT1A receptor subtype, promotes axonal transport of mitochondria in cultured hippocampal neurons by increasing Akt activity, and consequently decreasing glycogen synthase kinase (GSK3beta) activity. This finding suggests a critical ro...

Here we investigate the contribution of striatal dopamine receptors (D1) to the influence of reward-magnitude on learning. Pigeons (Columba livia) were trained on a discrimination-task with two pairs of stimuli; correct discrimination resulted in a large reward in one pair of stimuli and in a small reward in the other pair. Acquisition of the discrimination-task was accompanied by intracranial ...

The role of dopamine in regulating spinal cord function is receiving increasing attention, but its actions on spinal motor networks responsible for rhythmic behaviors remain poorly understood. Here, we have explored the modulatory influence of dopamine on locomotory central pattern generator (CPG) circuitry in the spinal cord of premetamorphic Xenopus laevis tadpoles. Bath application of exogen...