Hebbian induction of long-term potentiation of Aplysia sensorimotor synapses: partial requirement for activation of an NMDA-related receptor

Proc Biol Sci. 1994 Mar 22;255(1344):215-21. doi: 10.1098/rspb.1994.0031.


Long-term potentiation (LTP) of Aplysia sensorimotor synapses in cell culture can be induced by pairing sensory neuron activity with depolarization of the motorneuron. This pairing-induced LTP is prevented by perfusion with D,L-2-amino-5-phosphononovalerate (APV), a selective antagonist for the N-methyl-D-asparate (NMDA) subclass of glutamate receptors. Repeated pairing of presynaptic activity with postsynaptic depolarization induces LTP comprising both APV-sensitive and APV-insensitive components. Infusing BAPTA, a selective Ca2+ chelator, into the postsynaptic motoneuron completely blocks pairing-induced LTP. These results demonstrate that Aplysia sensorimotor synapses are capable of hebbian LTP-similar to that exhibited by synapses in the mammalian hippocampus - and suggest a role for this type of synaptic plasticity in classical conditioning of the defensive withdrawal reflex of Aplysia.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology*
  • Animals
  • Aplysia
  • Calcium / metabolism
  • Cells, Cultured
  • Egtazic Acid / analogs & derivatives
  • Egtazic Acid / pharmacology
  • Evoked Potentials / drug effects
  • Evoked Potentials / physiology
  • Long-Term Potentiation / drug effects
  • Long-Term Potentiation / physiology*
  • Membrane Potentials / drug effects
  • Membrane Potentials / physiology
  • Motor Neurons / drug effects
  • Motor Neurons / physiology*
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors
  • Receptors, N-Methyl-D-Aspartate / physiology*
  • Synapses / drug effects
  • Synapses / physiology*
  • Time Factors


  • Receptors, N-Methyl-D-Aspartate
  • Egtazic Acid
  • 2-Amino-5-phosphonovalerate
  • 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid
  • Calcium