title: Dark exposure extends the integration window for spike-timing-dependent plasticity.
abstract: Metaplasticity, the adaptive changes of long-term potentiation (LTP) and long-term depression (LTD) in response to fluctuations in neural activity is well documented in visual cortex, where dark rearing shifts the frequency threshold for the induction of LTP and LTD. Here we studied metaplasticity affecting spike-timing-dependent plasticity, in which the polarity of plasticity is determined not by the stimulation frequency, but by the temporal relationship between near-coincidental presynaptic and postsynaptic firing. We found that in mouse visual cortex the same regime of deprivation that restricts the frequency range for inducing rate-dependent LTD extends the integration window for inducing timing-dependent LTD, enabling LTD induction with random presynaptic and postsynaptic firing. Notably, the underlying mechanism for the changes in both rate-dependent and time-dependent LTD appears to be an increase of NR2b-containing NMDAR at the synapse. Thus, the rules of metaplasticity might manifest in opposite directions, depending on the plasticity-induction paradigms.
authors.affiliation: The Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland 21218, USA.
authors.forename: Yatu
authors.initials: Y
authors.lastname: Guo
authors.forename: Shiyong
authors.initials: S
authors.lastname: Huang
authors.forename: Roberto
authors.initials: R
authors.lastname: de Pasquale
authors.forename: Kevin
authors.initials: K
authors.lastname: McGehrin
authors.forename: Hey-Kyoung
authors.initials: HK
authors.lastname: Lee
authors.forename: Kanxing
authors.initials: K
authors.lastname: Zhao
authors.forename: Alfredo
authors.initials: A
authors.lastname: Kirkwood
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001703:Biophysics; D003624:Darkness; D004558:Electric Stimulation; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D018756:GABA Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology; D036881:Long-Term Synaptic Depression / Q000187:drug effects / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011724:Pyridazines / Q000494:pharmacology; D013997:Time Factors; D014793:Visual Cortex / Q000166:cytology*
chemical_list: D018691:Excitatory Amino Acid Antagonists; D018756:GABA Antagonists; D011724:Pyridazines; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; C049853:gabazine