Postsynaptic Induction of BDNF-Mediated Long-Term Potentiation.
Brain-derived neurotrophic factor (BDNF) and other neurotrophins are critically involved in long-term potentiation (LTP). Previous reports point to a presynaptic site of neurotrophin action. By imaging dentate granule cells in mouse hippocampal slices, we identified BDNF-evoked Ca2+ transients in dendrites and spines, but not at presynaptic sites. Pairing a weak burst of synaptic stimulation with a brief dendritic BDNF application caused an immediate and robust induction of LTP. LTP induction required activation of postsynaptic Ca2+ channels and N-methyl-d-aspartate receptors and was prevented by the blockage of postsynaptic Ca2+ transients. Thus, our results suggest that BDNF-mediated LTP is induced postsynaptically. Our finding that dendritic spines are the exclusive synaptic sites for rapid BDNF-evoked Ca2+ signaling supports this conclusion.
Kovalchuk
Yury
Y
Institut für Physiologie, Ludwig-Maximilians Universität München, 80336 München, Germany.
Hanse
Eric
E
Kafitz
Karl W
KW
Konnerth
Arthur
A
D000200:Action Potentials; D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling; D003712:Dendrites / Q000187:drug effects / Q000502:physiology*; D018891:Dentate Gyrus / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D019706:Excitatory Postsynaptic Potentials; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D018408:Patch-Clamp Techniques; D019580:Perforant Pathway; D020813:Receptor, trkB / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013569:Synapses / Q000187:drug effects / Q000502:physiology*
D019208:Brain-Derived Neurotrophic Factor; D016194:Receptors, N-Methyl-D-Aspartate; D020813:Receptor, trkB; D002118:Calcium