Mediation of Classical Conditioning in Aplysia californica by Long-Term Potentiation of Sensorimotor Synapses
Geoffrey G. Murphy,
David L. Glanzman
*
Long-term potentiation (LTP) is considered an important neuronal
mechanism of learning and memory. Currently, however, there is no
direct experimental link between LTP of an identified synapse and
learning. A cellular analog of classical conditioning in
Aplysia was used to determine whether this form of
invertebrate learning involves
N-methyl-D-aspartate (NMDA)-type LTP. The NMDA
receptor-antagonist DL-2-amino-5-phosphonovalerate
significantly disrupted synaptic enhancement after associative training
but did not disrupt synaptic enhancement after nonassociative training.
Thus, classical conditioning in Aplysia appears to be
mediated, in part, by LTP due to activation of NMDA-related receptors.
G. G. Murphy, Interdepartmental Graduate Program in
Neuroscience, School of Medicine, University of California, Los
Angeles, CA 90095, USA.
D. L. Glanzman, Department of Physiological Science and Brain
Research Institute, University of California, 2859 Slichter Hall, Los
Angeles, CA 90095-1568, USA.
*
To whom correspondence should be addressed. E-mail:
dglanzman{at}physci.ucla.edu
