Search results for "corpus"
showing 10 items of 698 documents
Fluency and rule breaking behaviour in the frontal cortex
2020
Design (DF) and phonemic fluency tests (FAS; D-KEFS, 2001) are commonly used to investigate voluntary generation. Despite this, several important issues remain poorly investigated. In a sizeable sample of patients with focal left or right frontal lesion we established that voluntary generation performance cannot be accounted for by fluid intelligence. For DF we found patients performed significantly worse than healthy controls (HC) only on the switch condition. However, no significant difference between left and right frontal patients was found. In contrast, left frontal patients were significantly impaired when compared with HC and right frontal patients on FAS. These lateralization findin…
Understanding Cannabinoid Psychoactivity with Mouse Genetic Models
2007
Marijuana and its main psychotropic ingredient Δ9-tetrahydrocannabinol (THC) exert a plethora of psychoactive effects through the activation of the neuronal cannabinoid receptor type 1 (CB1), which is expressed by different neuronal subpopulations in the central nervous system. The exact neuroanatomical substrates underlying each effect of THC are, however, not known. We tested locomotor, hypothermic, analgesic, and cataleptic effects of THC in conditional knockout mouse lines, which lack the expression of CB1 in different neuronal subpopulations, including principal brain neurons, GABAergic neurons (those that release γ aminobutyric acid), cortical glutamatergic neurons, and neurons expres…
Aspirin protects striatal dopaminergic neurons from neurotoxin-induced degeneration: an in vivo microdialysis study.
2006
The effect of aspirin on dopaminergic neuronal damage induced by in vivo infusion of 1-methyl-4-phenylpiridinium iodide (MPP(+)) and 6-hydroxydopamine (6-OHDA) was studied in rats, using microdialysis. Rat striata were perfused with 1 mM MPP(+) or 6-OHDA for 10 min, causing peak levels of dopamine (DA) in the dialytic fluid, after 40 min. After 24 h, 1 mM MPP(+) was perfused again for 10 min and DA levels measured in the dialytic fluid, as an index of neuronal cell integrity. Pretreatment with Aspidol (lysine acetylsalicylate), 180 mg/kg i.p., 1 h before MPP(+) or 6-OHDA perfusion, did not modify DA extracellular output, on day 1, but restored MPP(+)-induced DA release on day 2, indicating …
Analysis of ceftriaxone and ceftazidime distribution in cerebrospinal fluid of and cerebral extracellular space in awake rats by in vivo microdialysis
1995
In vivo microdialysis was used to estimate the extracellular concentrations of ceftazidime and ceftriaxone, two expanded-spectrum cephalosporins commonly used in the treatment of bacterial meningitis, in two brain regions (the right corpus striatum and the left lateral ventricle) of awake, freely moving rats. Antibiotics were administered by constant intravenous infusion at 18 mg/h until steady-state levels were reached. Ceftriaxone levels measured at the steady state in the extracellular space of the corpus striatum (0.80 ± 0.17 J.tg/ml) were statistically equivalent to those obtained in the cerebrospinal fluid of the lateral ventricle (0.71 ± 0.15 J.tg/ml). The ratios of these levels in t…
Tetrahydroisoquinolines as dopaminergic ligands: 1-Butyl-7-chloro-6-hydroxy-tetrahydroisoquinoline, a new compound with antidepressant-like activity …
2009
International audience; Three series of 1-substituted-7-chloro-6-hydroxy-tetrahydroisoquinolines (1-butyl-, 1-phenyl- and 1-benzyl derivatives) were prepared to explore the influence of each of these groups at the 1-position on the affinity for dopamine receptors. All the compounds displayed affinity for D(1)-like and/or D(2)-like dopamine receptors in striatal membranes, and were unable to inhibit [(3)H]-dopamine uptake in striatal synaptosomes. Different structure requirements have been observed for adequate D(1) or D(2) affinities. This paper details the synthesis, structural elucidation, dopaminergic binding assays, structure-activity relationships (SAR) of these three series of isoquin…
Quantitative assessment of stereotyped and challenged locomotion after lesion of the striatum: a 3D kinematic study in rats.
2009
Background Although the striatum is in position to regulate motor function, the role of the structure in locomotor behaviour is poorly understood. Therefore, a detailed analysis of locomotion- and obstacle avoidance-related parameters was performed after unilateral lesion of the striatum in rats. Methods and Results Using the three dimensional motion capture technology, kinematics of walking and clearing obstacles, head and body orientation were analyzed before and up to 60 days after the lesion. Recordings were performed in treadmill running rats with or without obstacles attached to the treadmill belt. The lesion, which was induced by the direct injection of the mitochondrial toxin malona…
Effects of risperidone on the acquisition and reinstatement of the conditioned place preference induced by MDMA
2013
Some users of 3,4-methylenedioxymethylamphetamine (MDMA or ecstasy) abuse this drug and/or become concerned about their use. These individuals would benefit greatly from the development of pharmacological strategies to reduce MDMA consumption. We have previously observed that antipsychotics block acquisition and expression of the conditioned place preference (CPP) induced by MDMA, though they do not modify priming-induced reinstatement of MDMA-induced CPP after extinction. In the present study we have evaluated the capacity of the mixed serotonin (5-HT2A)/dopamine (DA D2) antagonist risperidone to block acquisition and reinstatement of MDMA induced-CPP. Adolescent male mice conditioned with…
Toll-like receptor 4 defective mice carrying point or null mutations do not show increased susceptibility toCandida albicansin a model of hematogenou…
2006
We have studied the role of TLR4 in murine defenses against Candida albicans in two TLR4-defective mouse strains: C3H/HeJ mice which have defective TLR4 signaling, and TLR4-/- knockout mice. Both TLR4-defective mice strains experimentally infected with virulent C. albicans cells showed no significant difference in survival as compared with their respective controls. Recruitment of neutrophils to the peritoneal cavity of i.p. infected mice was not affected in TLR4-/-animals, but significantly enhanced in C3H/HeJ mice, compared with their control mice. In vitro production of TNF-alpha by macrophages from both types of TLR4-defective mice, in response to yeasts and hyphae of C. albicans, was n…
Critical role of nitric oxide on nicotine-induced hyperactivation of dopaminergic nigrostriatal system: electrophysiological and neurochemical eviden…
2010
Nicotine, the main psychoactive ingredient in tobacco, stimulates dopamine (DA) function, increasing DA neuronal activity and DA release. DA is involved in both motor control and in the rewarding and reinforcing effects of nicotine; however, the complete understanding of its molecular mechanisms is yet to be attained. Substantial evidence indicates that the reinforcing properties of drugs of abuse, including nicotine, can be affected by the nitric oxide (NO) system, which may act by modulating central dopaminergic function. In this study, using single cell recordings in vivo coupled with microiontophoresis and microdialysis in freely moving animals, the role of NO signaling on the hyperacti…
Neuroprotective Properties of Mildronate, a Small Molecule, in a Rat Model of Parkinson’s Disease
2010
Previously, we have found that mildronate [3-(2,2,2-trimethylhydrazinium) propionate dihydrate], a small molecule with charged nitrogen and oxygen atoms, protects mitochondrial metabolism that is altered by inhibitors of complex I and has neuroprotective effects in an azidothymidine-neurotoxicity mouse model. In the present study, we investigated the effects of mildronate in a rat model of Parkinson’s disease (PD) that was generated via a unilateral intrastriatal injection of the neurotoxin 6-hydroxydopamine (6‑OHDA). We assessed the expression of cell biomarkers that are involved in signaling cascades and provide neural and glial integration: the neuronal marker TH (tyrosine hydroxylase); …