title: Spatiotemporal characteristics of synaptic EPSP summation on the dendritic trees of hippocampal CA1 pyramidal neurons as revealed by laser uncaging stimulation.
abstract: Synaptic strength is modified by the temporal coincidence of synaptic inputs without back-propagating action potentials (BPAPs) in CA1 pyramidal neurons. In order to clarify the interactive mechanisms of associative long-term potentiation (LTP) without BPAPs, local paired stimuli were applied to the dendrites using high-speed laser uncaging stimulation equipment. When the spatial distance between the paired stimuli was <10 micrometer, nonlinear amplification in excitatory postsynaptic potential summation was observed. In the time window from -20 to 20 ms, supralinear amplification was observed. Supralinear amplification was modulated by antagonist of voltage-gated Na(+)/Ca(2+) channels and NMDA-type glutamate receptors. These results are closely related to the spatiotemporal-characteristics of associative LTP without BPAPs. This study proposes an essential aspect of dendritic information processing.
authors.affiliation: Brain Science Institute, Tamagawa University, 6-1-1 Tamagawagakuen, Machida, Tokyo, 194-8610 Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoneyama
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fukushima
authors.forename: Minoru
authors.initials: M
authors.lastname: Tsukada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Aihara
keywords: Dendrite; EPSP summation; Hippocampus; Spatiotemporal information; Supralinear amplification; Uncaging