G. E. Chouvet

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High frequency stimulation (130 Hz) of the subthalamic nucleus has dramatic beneficial motor effects in severe parkinsonian patients. However, the mechanisms underlying these clinical results remain obscure. The objective of the present work was to study the neurochemical changes induced in rats by high frequency stimulation of the subthalamic nucleus by(More)
Midbrain dopamine neurons in vivo discharge in a single-spike firing pattern or in a burst-firing pattern. Such activity in vivo strikingly contrasts with the pacemaker activity of the same dopamine neurons recorded in vitro. We have recently shown that burst activity in vivo of midbrain dopamine neurons is due to the local activation of excitatory amino(More)
The influence of the medial prefrontal cortex (PFC) on mesolimbic dopamine activity was studied with electrophysiological techniques and in vivo voltammetry in the chloral hydrate-anesthetized male rat. Glutamate injected into the PFC selectively increased burst firing of single dopamine cells in the ventral tegmental area and enhanced the release of(More)
Dopamine is involved in motivation, memory, and reward processing. However, it is not clear whether the activity of dopamine neurons is related or not to vigilance states. Using unit recordings in unanesthetized head restrained rats we measured the firing pattern of dopamine neurons of the ventral tegmental area across the sleep–wake cycle. We found these(More)
Extracellular electrophysiological recordings in freely moving cats have shown that serotonergic neurons from the dorsal raphe nucleus (DRN) fire tonically during wakefulness, decrease their activity during slow wave sleep (SWS), and are nearly quiescent during paradoxical sleep (PS). The mechanisms at the origin of the modulation of activity of these(More)
Striatal medium-sized spiny neurons (MSNs) integrate and convey information from the cerebral cortex to the output nuclei of the basal ganglia. Intracellular recordings from anesthetized animals show that MSNs undergo spontaneous transitions between hyperpolarized and depolarized states. State transitions, regarded as necessary for eliciting action(More)
Amino acids were pressure-ejected in the ventral tegmental area of rats which were anesthetized with chloral hydrate and treated with pargyline. The extracellular dopamine concentration was recorded from the nucleus accumbens with an electrochemically treated carbon fiber electrode combined either with differential normal pulse voltammetry or with(More)
The effects of the selective 5-HT1A receptor agonist (R)-8-hydroxy-2(di-n-propylamino)tetralin [(R)-8-OH-DPAT] and the novel 5-HT1A antagonist (S)-5-fluoro-8-hydroxy-2-(dipropylamino)-tetralin [(S)-UH-301] were studied with regard to the firing pattern of single mesencephalic dopamine (DA) neurons with extracellular recording techniques in chloral hydrate(More)
The aim of this study was to examine the afferents to the rat locus coeruleus by means of retrograde and anterograde tracing experiments using cholera-toxin B subunit and phaseolus leucoagglutinin. To obtain reliable injections of cholera-toxin B in the locus coeruleus, electrophysiological recordings were made through glass micropipettes containing the(More)
Tract-tracing and electrophysiology studies have revealed that major inputs to the nucleus locus coeruleus (LC) are found in two structures, the nucleus paragigantocellularis (PGi) and the perifascicular area of the nucleus prepositus hypoglossi (PrH), both located in the rostral medulla. Minor afferents to LC were found in the dorsal cap of the(More)