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Gamma frequency network oscillations are assumed to be important in cognitive processes, including hippocampal memory operations, but the precise functions of these oscillations remain unknown. Here, we examine the cellular and network mechanisms underlying carbachol-induced fast network oscillations in the hippocampus in vitro, which closely resemble(More)
Somatodendritic dopamine (DA) release from neurons of the midbrain represents a nonclassical form of neuronal signaling. We assessed characteristics of DA release during electrical stimulation of the substantia nigra pars compacta (SNc) in guinea pig midbrain slices. With the use of parameters optimized for this region, we compared stimulus-induced(More)
Dopamine (DA) is released from somatodendritic sites of neurons in the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA), where it has neuromodulatory effects. The aim of this study was to evaluate the role of D2 autoreceptor inhibition in the regulation of this somatodendritic release in each region. Fast cyclic voltammetry at carbon(More)
Somatodendritic dopamine (DA) released in substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA) may mediate extrasynaptic neuronal signaling. The concentration of extracellular DA ([DA]o) attained during somatodendritic activation will be governed by the density of release sites and properties of DA uptake. We evaluated these factors in(More)
In this study, we compare the electrically evoked, somatodendritic release of dopamine (DA) with axonal release of serotonin (5-HT) in the substantia nigra (SN) and ventral tegmental area (VTA) in vitro by using fast-scan cyclic voltammetry with carbon-fibre microelectrodes. Furthermore, we have examined transmitter release in these regions in guinea-pig(More)
The putamen of the human striatum is a heterogeneous nucleus that contains the primary site of loss of dopamine (DA) in Parkinson's disease (PD). Furthermore, different functional domains of the putamen are heterogeneously susceptible to DA loss, and yet the dynamic regulation of extracellular DA concentration ([DA](o)) and comparison between domains has(More)
Intracellular recordings were performed in vitro from both pars compacta and pars reticulata neurones of the substantia nigra, and their postsynaptic responses to electrical stimulation within the nucleus were analysed. Intracellular staining by biocytin was used to reveal the morphology and location of the recorded neurone and its position and distance to(More)
Within the substantia nigra, the dendrites of dopaminergic neurons that project to the striatum appear to play an active and nonclassical role in the physiology of the neuron in that they release transmitter and protein, but little is known of the factors controlling release of substances from these dendrites. In this study, we show that(More)
To ascertain the extent to which neuronal firing pattern in the subthalamic nucleus (STN) is determined by afferent inputs, a comparison was made between STN neurons recorded in vivo and in vitro (a largely denervated preparation). In vivo, the majority of cells exhibited an irregular firing pattern, although some showed evidence of burst firing. In(More)
In the substantia nigra pars compacta neurons can be classified in two sub-populations. In this study the distinguishing criteria have been the presence of four distinct calcium-dependent potentials, two each generated selectively and exclusively in each cell type. One class of cells, found in the more caudal pars compacta, displays calcium-mediated, slow(More)