| Figure 4. |
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| Distribution of neurotransmitter in intra- and extra-synaptic compartments under three conditions: a) under baseline conditions, ongoing electrophysiological activity regulates intra-synaptic transmitter concentrations - although much of the released transmitter is cleared by high-affinity uptake, a fraction does escape into the extra-synaptic compartment and can be monitored by in vivo microdialysis and voltammetry, b) under conditions of increased electrophysiological activity, intra-synaptic transmitter concentrations increase and there is greater overflow of the transmitter from intra- to extra-synaptic compartment, c) under conditions of reverse transport, extra-synaptic transmitter concentrations increase whereas intra-synaptic concentrations may be largely unaffected. |
published 2000