Reversing cerebellar long-term depression
AUTOR(ES)
Lev-Ram, Varda
FONTE
National Academy of Sciences
RESUMO
The discovery of a postsynaptically expressed form of cerebellar parallel fiber–Purkinje cell long-term potentiation (LTP) raises the question whether this is the long-sought resetting mechanism for long-term depression (LTD). Extracellular monitoring of PC spikes enables stable prolonged recordings of parallel fiber–Purkinje cell synaptic efficacy. LTD, saturated by repeated induction protocols, can be reversed by a single round of postsynaptic LTP or nitric oxide (NO), enabling LTD to be reinduced. Conversely, after postsynaptic LTP has been saturated, one round of LTD permits fresh postsynaptic LTP. By contrast, after saturation of LTD, induction of presynaptic LTP or application of forskolin leaves LTD still saturated. Likewise, presynaptic LTP cannot be reversed by LTD. Therefore postsynaptic LTP mediated by NO without postsynaptic Ca2+ elevation, unlike presynaptic LTP mediated by cAMP, is a true counterbalance to LTD mediated by coincidence of NO plus postsynaptic Ca2+
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=307680Documentos Relacionados
- Long-term potentiation and long-term depression: a clinical perspective
- Hippocampal long-term depression and long-term potentiation encode different aspects of novelty acquisition
- Induction of long-term depression and rebound potentiation by inositol trisphosphate in cerebellar Purkinje neurons
- Quantification of spread of cerebellar long-term depression with chemical two-photon uncaging of glutamate
- Homosynaptic long-term depression: A mechanism for memory?
