Adenosine signalling at immature parallel fibre–Purkinje cell synapses in rat cerebellum
AUTOR(ES)
Atterbury, Alison
FONTE
Blackwell Science Inc
RESUMO
The purine adenosine is an extracellular signalling molecule involved in a large number of physiological and pathological conditions throughout the mammalian brain. However little is known about how adenosine release and its subsequent clearance change during brain development. We have combined electrophysiology and microelectrode biosensor measurements to investigate the properties of adenosine signalling at early stages of cerebellar development, when parallel fibre–Purkinje cell synapses have recently been formed (postnatal days 9–12). At this stage of development, we could detect little or no inhibitory A1 receptor tone in basal conditions and during trains of stimuli. Addition of pharmacological agents, to inhibit adenosine clearance, had only minor effects on synaptic transmission suggesting that under basal conditions, the concentration of adenosine moving in and out of the extracellular space is small. Active adenosine release was stimulated with hypoxia and trains of electrical stimuli. Although hypoxia released significant concentrations of adenosine, the release was delayed and slow. No adenosine release could be detected following electrical stimulation in the molecular layer. In conclusion, at this stage of development, although adenosine receptors and the mechanisms of adenosine clearance are present there is very little adenosine release.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2766653Documentos Relacionados
- Synaptic modification of parallel fibre-Purkinje cell transmission in in vitro guinea-pig cerebellar slices.
- Glutamate as a candidate retrograde messenger at interneurone-Purkinje cell synapses of rat cerebellum.
- The secondary spikes of climbing fibre responses recorded from Purkinje cell somata in cat cerebellum.
- The secondary spikes of climbing fibre responses recorded from Purkinje cell axons in cat cerebellum.
- Uniform olivocerebellar conduction time underlies Purkinje cell complex spike synchronicity in the rat cerebellum.