Lesions of the lateral habenula produce anxiolytic effects in a rat model of Parkinson's disease.

: This study was designed to investigate the effects of lateral habenula (LHb) lesion on anxiety-like behaviors in parkinsonian rats.: Anxiety-like behaviors were assessed by the open field and elevated plus maze (EPM) tests in control, medial forebrain bundle (MFB)-lesioned, MFB- and LHb-lesioned and MFB-lesioned and LHb sham-lesioned rats, respectively. The levels of extracellular dopamine (DA), serotonin (5-HT) and noradrenaline (NA) in the basolateral amygdala (BLA) were measured by microdialysis and neurochemistry.

Activation and Blockade of Serotonin-4 Receptors in the Lateral Habenula Produce Antidepressant Effects in the Hemiparkinsonian Rat.

Background: The 5-hydroxytryptamine (5-HT) neurotransmitter system and lateral habenula (LHb) are involved in the regulation of depression, while the mechanisms remain to be clarified.

Objectives: The effects and possible mecha-nism underlying activation or blockade of 5-HT4 receptors (5-HT4Rs) in the LHb in depression were investigated by behavioral and neurochemical methods based on a Parkinson's disease (PD) rat model.

Method: 6-Hydroxydopamine (6-OHDA) was injected unilaterally into the substantia nigra pars compacta to establish the PD rat model.

Activation and blockade of serotonin receptors in the lateral habenula improve working memory in unilateral 6-hydroxydopamine-lesioned Parkinson's rats.

: The aim of the present study was to investigate the effects and mechanism of 6-hydroxydopamine (6-OHDA) lesions and serotonin  (5-HT) receptors in the lateral habenula (LHb) on Parkinson's disease (PD) related working memory. : The working memory was measured by the T-maze rewarded alternation test in sham rats and rats with unilateral 6-OHDA lesions of substantia nigra pars compacta (SNc). The concentrations of dopamine (DA), noradrenaline (NA) and 5-HT in the related brain regions were measured by neurochemistry.

Serotonin₆ Receptors in the Prelimbic Cortex are Involved in the Regulation of Anxiety-Like Behaviors in the Rat 6-Hydroxydopamine Parkinson’s Disease Model.

The role of serotonin₆ (5-HT₆) receptors in the regulation of anxiety is poorly understood, particularly in Parkinson’s disease-related anxiety. Here we examined whether 5-HT₆ receptors in the prelimbic cortex (PrL) involve in the regulation of anxiety-like behaviors in sham-operated rats and rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle. The lesion induced anxiogenic responses as measured by the open-field and elevated-plus maze tests compared to sham-operated rats.

Involvement of prelimbic 5-HT receptors in the regulation of anxiety-like behaviors in hemiparkinsonian rats.

Objective: At present, little is known about the role of serotonin (5-HT) receptor in anxiety, particularly in Parkinson's disease-related anxiety. Here, we tested whether 5-HT receptors in the prelimbic (PrL) cortex are involved in the regulation of anxiety-like behaviors in sham-operated rats and rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle (MFB).

Methods: The open field and elevated plus maze (EPM) tests were performed to study the influence of MFB lesion and intra-PrL injection of 5-HT agonist AS19 (0.

Activation and blockade of basolateral amygdala 5-HT receptor produce anxiolytic-like behaviors in an experimental model of Parkinson's disease.

Although the basolateral amygdala (BLA) and serotonin (5-HT) receptor are involved in modulation of anxiety, their roles in Parkinson' disease (PD)-related anxiety are still unknown. Thus we perform this study to examine the involvement of BLA 5-HT receptor on anxiety in unilateral 6-hydroxydopamine-induced PD rats. The lesion of the medial forebrain bundle (MFB) induced anxiety-like behaviors, and decreased the basal firing rate of BLA glutamate neurons and dopamine (DA) levels in tissues of the medial prefrontal cortex (mPFC), amygdala and ventral part of hippocampus (vHip) in rats.

Identification of metabolite biomarkers for L-DOPA-induced dyskinesia in a rat model of Parkinson's disease by metabolomic technology.

L-DOPA-induced dyskinesia (LID) is a frequent complication of chronic L-DOPA therapy in the clinical treatment of Parkinson's disease (PD). The pathogenesis of LID involves complex molecular mechanisms in the striatum. Metabolomics can shed light on striatal metabolic alterations in LID.

Lesions of the lateral habenula improve working memory performance in hemiparkinsonian rats.

The lateral habenula (LHb) is an important structure involved in various brain functions, because it controls the activity of dopaminergic and serotonergic systems in the midbrain. The impairment of working memory commonly occurs in Parkinson's disease; however, it is not clear whether the LHb involves in the regulation of working memory in rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle (MFB). In this study, we found that the MFB lesions in rats decreased choice accuracy as measured by the T-maze rewarded alternation test compared to control rats, indicating the induction of working memory impairment, and decreased dopamine (DA) levels in the medial prefrontal cortex (mPFC), hippocampus and amygdala.

Prelimbic α-adrenoceptors are involved in the regulation of depressive-like behaviors in the hemiparkinsonian rats.

At present, it is not clear whether α-adrenoceptors in the prelimbic cortex (PrL) are involved in Parkinson's disease-related depression. Here we examined effects of PrL α-adrenoceptors on depressive-like behaviors in rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle. The lesion induced depressive-like responses as measured by the sucrose preference and forced swim tests compared to sham-operated rats.

Involvement of lateral habenula α1 subunit-containing GABA receptor-mediated inhibitory transmission in the regulation of depression-related behaviors in experimental Parkinson's disease.

The lateral habenula (LHb) plays an important role in the regulation of depression. At present, it is not clear whether GABA receptor-mediated inhibitory transmission in the LHb is involved in Parkinson's disease (PD)-associated depression. In this study, unilateral 6-hydroxydopamine lesions of the substantia nigra in rats induced depressive-like behaviors and led to hyperactivity of LHb neurons compared to sham-operated rats, which attribute to depletion of dopamine, and decreased synthesis and release of GABA and increased release of glutamate in the LHb.

Activation and blockade of serotonin receptors in the dorsal hippocampus enhance T maze and hole-board performance in a unilateral 6-hydroxydopamine rat model of Parkinson's disease.

The role of dorsal hippocampus (DH) serotonin (5-HT) receptors in memory is unknown, particularly in memory impairment of Parkinson's disease. We tested here effects of activation and blockade of DH 5-HT receptors on working and hippocampus-dependent memories in rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle. The lesion induced working and hippocampus-dependent memory impairments as measured by the T-maze rewarded alternation and hole-board tests, and decreased dopamine (DA) levels in the striatum, medial prefrontal cortex (mPFC), DH and amygdala.

Activation and blockade of prelimbic 5-HT6 receptors produce different effects on depressive-like behaviors in unilateral 6-hydroxydopamine-induced Parkinson's rats.

The role of prelimbic (PrL) 5-HT6 receptors in depression is poorly understood, particularly in Parkinson's disease-related depression. Here we reported that 6-hydroxydopamine lesions in rats decreased sucrose preference and increased immobility time as measured by the sucrose preference and forced swim tests when compared to sham-operated rats, indicating the induction of depressive-like behaviors. Intra-PrL injection of 5-HT6 receptor agonist WAY208466 induced depressive-like responses in sham-operated rats, and produced antidepressant-like effects in the lesioned rats.

Serotonin7 receptors in the lateral habenular nucleus regulate depressive-like behaviors in the hemiparkinsonian rats.

Preclinical studies indicate that serotonin7 (5-HT7) receptors may regulate depressive-like behaviors. Depression is a common symptom in Parkinson's disease (PD); however, its pathophysiology is unclear. Here we examined whether 5-HT7 receptors in the lateral habenular nucleus (LHb) involve in the regulation of PD-related depression.