Neurons that utilize dopamine (DA) as a neurotransmitter have attracted great interest because of their involvement in the behavioral, endocrine and descending control of major brain functions. DA is known to exert its physiological effects on target neurons through D1-like (D1 and D5) and D2-like (D2, D3 and D4) receptor subtypes. To better understand the DA modulation of brain functions, the ...

Alternative splicing of the dopamine D2 receptor gene produces two distinct isoforms referred to as D2long (D2L) and D2short (D2S). In mesencephalic dopamine neurons, inhibition of the firing rate through activation of somatodendritic D2 receptors and blockade of neurotransmitter release through stimulation of terminal D2 receptors represent major roles of D2 autoreceptors. Recently, data obtai...

The present study sought to determine, in more detail, the effects of an unselective and a selective adenosine A(2A) receptor blockade on catalepsy induced by a blockade of dopamine D1 or D2 receptors in rats. The results demonstrated that systemic administration of the unselective A1/A2 receptor antagonist, theophylline and the selective A(2A) receptor antagonist, CSC potently reversed catalep...

Recently evidence has been presented that adenosine A2A and dopamine D2 receptors form functional heteromeric receptor complexes as demonstrated in human neuroblastoma cells and mouse fibroblast Ltk- cells. These A2A/D2 heteromeric receptor complexes undergo coaggregation, cointernalization, and codesensitization on D2 or A2A receptor agonist treatments and especially after combined agonist tre...

Dysregulation of dopamine transmission is thought to contribute to schizophrenic psychosis and drug dependence. Dopamine release is regulated by D2 dopamine autoreceptors, and D2 receptor ligands are used to treat psychosis and addiction. To elucidate the long-term effects of D2 autoreceptor activity on dopamine signaling, dopamine overflow evoked by single or paired-pulse stimulation was compa...

Dopamine is an important neurotransmitter in the central nervous system of both Drosophila and mammals. Despite the evolutionary distance, functional parallels exist between the fly and mammalian dopaminergic systems, with both playing roles in modulating locomotor activity, sexual function, and the response to drugs of abuse. In mammals, dopamine exerts its effects through either dopamine 1-li...

LEK-8829 [9,10-didehydro-N-methyl-(2-propynyl)-6-methyl-8- aminomethylergoline bimaleinate] is an antagonist of dopamine D2 receptors and serotonin (5-HT)2 and 5-HT1A receptors in intact animals and a D1 receptor agonist in dopamine-depleted animals. In the present study, we used rats with unilateral striatal lesions with ibotenic acid (IA) to investigate the dopamine receptor activities of LEK...

The inability to learn an adaptive coping strategy in a novel stressful condition leads to dysfunctional stress coping, a marker of mental disturbances. This study tested the involvement of dorsal striatal dopamine receptors in the dysfunctional coping with the Forced Swim test fostered by a previous experience of reduced food availability. Adult male mice were submitted to a temporary (12 days...

Dopamine is a neurotransmitter implicated in several brain functions, including vision. In the present study, we investigated the impacts of the lack of D2 dopamine receptors on the structure and function of the primary visual cortex (V1) of D2-KO mice using optical imaging of intrinsic signals. Retinotopic maps were generated in order to measure anatomo-functional parameters such as V1 shape, ...

The electrophysiological properties of distinct subpopulations of striatal medium-sized spiny neurons (MSSNs) were compared using enhanced green fluorescent protein as a reporter gene for identification of neurons expressing dopamine D1 and D2 receptor subtypes in mice. Whole-cell patch-clamp recordings in slices revealed that passive membrane properties were similar in D1 and D2 cells. All MSS...