Presynaptic BDNF promotes postsynaptic long-term potentiation in the dorsal striatum.
Brain-derived neurotrophic factor (BDNF) facilitates the formation of long-term potentiation (LTP) in hippocampus, but whether this involves release from presynaptic versus postsynaptic pools is unclear. We therefore tested whether BDNF is essential for LTP in dorsal striatum, a structure in which the neurotrophin is present only in afferent terminals. Whole-cell recordings were collected from medium spiny neurons in striatal slices prepared from adult mice. High-frequency stimulation (HFS) of neocortical afferents produced a rapid and stable NMDA receptor-dependent potentiation. The ratio of AMPA to NMDA receptor-mediated components of the EPSPs was substantially increased after inducing potentiation, suggesting that the response enhancement involved postsynaptic changes. In accord with this, paired-pulse response ratios, a measure of transmitter release kinetics, were reduced by elevated calcium but not by LTP. Infusion of the BDNF scavenger TrkB-Fc blocked the formation of potentiation, beginning with the second minute after HFS, without reducing responses to HFS. These results suggest that presynaptic pools of BDNF can act within 2 min of HFS to support the formation of a postsynaptic form of LTP in striatum.
Jia
Yousheng
Y
Department of Anatomy, University of California, Irvine, California 92697-4291, USA.
Gall
Christine M
CM
Lynch
Gary
G
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000008:administration & dosage / Q000494:pharmacology*; D003342:Corpus Striatum / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D004558:Electric Stimulation; D004594:Electrophysiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D017729:Presynaptic Terminals / Q000187:drug effects*; D020813:Receptor, trkB / Q000037:antagonists & inhibitors; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D013569:Synapses / Q000187:drug effects*
D019208:Brain-Derived Neurotrophic Factor; D018691:Excitatory Amino Acid Antagonists; D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; D020813:Receptor, trkB