Visualization of changes in presynaptic function during long-term synaptic plasticity.
Controversy exists regarding the site of modification of synaptic transmission during long-term plasticity in the mammalian hippocampus. Here we used a fluorescent marker of presynaptic activity, FM 1-43, to directly image changes in presynaptic function during both short-term and long-term forms of plasticity at presynaptic boutons of CA3-CA1 excitatory synapses in acute hippocampal slices. We demonstrated enhanced presynaptic function during long-term potentiation (LTP) induced either chemically (with tetraethylammonium), or by high-frequency (200-Hz) electrical stimulation. Both of these forms of LTP required activation of L-type voltage-gated calcium channels and NMDA receptors in the postsynaptic CA1 neuron. These results thus implied that a long-lasting increase in the efficacy of synaptic transmission is likely to depend, at least in part, on enhanced transmitter release from the presynaptic neuron.
Zakharenko
S S
SS
Center for Neurobiology and Behavior, Howard Hughes Medical Institute, Columbia University, 722 West 168th Street, New York, New York 10032, USA.
Zablow
L
L
Siegelbaum
S A
SA
D000818:Animals; D004558:Electric Stimulation; D019706:Excitatory Postsynaptic Potentials; D005456:Fluorescent Dyes; D006624:Hippocampus / Q000502:physiology / Q000648:ultrastructure; D066298:In Vitro Techniques; D017774:Long-Term Potentiation; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009473:Neuronal Plasticity; D017729:Presynaptic Terminals / Q000502:physiology*; D011726:Pyridinium Compounds; D000644:Quaternary Ammonium Compounds
C073804:FM1 43; D005456:Fluorescent Dyes; D011726:Pyridinium Compounds; D000644:Quaternary Ammonium Compounds