User:Rob Malenka/Proposed/Long-term depression

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This article is in preparation.

Long-term depression (LTD) is a weakening of a synapse after a short series of presynaptic action potentials or asynchronous presynaptic and postsynaptic activity. LTD is distinguished in homosynaptic LTD, heterosynaptic LTD and associative LTD.

Types of LTD

  • homosynaptic LTD: LTD is confined to the synapse where the short series of action potentials arrived.
  • heterosynaptic LTD: LTD affects also other synapses of the respective cell.
  • associative LTD: Asynchronous pre- and postsynaptic increase of intracellular calcium causes LTD.

Occurrences of LTD

  • Cerebellum
    • Purkinje cells: Purkinje cells receive unspecific excitatory input from parallel fibers. But each purkinje cell receives a synapse from a single climbing fiber. Activation of a climbing fiber results in a reduction of the excitability of the according Purkinje cell. This LTD is related with the accomodation of the vestibo-ocular reflex to optical conditions.
  • Hippocampus

Mechanisms of LTD

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