Biology subjects

Ito, W.

Publications and source records attributed to Ito, W..

3 recordsLinked to original sources

bioRxiv2018

Observing fear enables plasticity of the dmPFC-BLA pathway during subsequent learning of inhibitory avoidance

Observing fear in others is a form of social distress. In mice, it leads to the formation of silent synapses in the prefrontal-amygdala pathway and enhances inhibitory avoidance learning at a later time. Here, we report that observing fear enabled ex vivo LTP. The unsilencing of silent synapses was the prevailing mechanism and the plasticity was occluded by inhibitory avoidance training. In free moving mice with OF experience, the inhibitory avoidance training transiently facilitated local field potentials evoked in BLA by stimulating the prefrontal afferents. The facilitation persisted during the first 4 hours after IA training, which is the time when IA memories consolidate. Thus, the OF-generated silent synapses enable plasticity that may enhance consolidation of IA memories.

neuroscience↗

bioRxiv2017

Impaired social contacts with familiar anesthetized conspecific in CA3-restricted BDNF knockout mice

Familiarity is the vital characteristic conveyed by social cues to determine behaviors towards conspecific. Here we characterize social contacts to familiar vs unfamiliar male conspecific, anesthetized to eliminate inter-male aggression. During initial 10 min (phase-1), subjects contacted demonstrators vigorously regardless of familiarity. During subsequent 80 min (phase-2), however, they contacted more with familiar than unfamiliar conspecifics. Then, this test was applied on highly aggressive mice with hippocampal CA3-restricted BDNF knockout (KO), in which aggression may mask other behaviors. KO showed less preference to contacting familiar conspecific than wild type (WT) during phase-2 but no differences during phase-1. Among non-social behaviors, eating duration was shorter in the presence of familiar than unfamiliar conspecific in WT, but same in KO. Additionally, KO exhibited reduced pain sensitization. Altogether, these findings suggest that KO has deficits in circuits that process social cues from familiar conspecifics and pain and, possibly, underlie empathy-like behaviors.

animal behavior and cognition↗

bioRxiv2017

Overexpression of Channelrhodopsin 2 interferes with the GABAb receptor-mediated depression of GABA release from the somatostatin-containing interneurons of the prefrontal cortex

Region and cell-type restricted expression of light activated ion channels is the indispensable tool to study properties of synapses in specific circuits and to monitor synaptic alterations by various stimuli including neuromodulators and behaviors, both ex vivo and in vivo. These analyses require the light-activated proteins or viral vectors for their delivery that do not interfere with the phenomenon under study. Here, we report a case of such interference in which the high-level expression of Channelrhodopsin-2 (ChR2) introduced in the somatostatin-positive GABAergic neurons (SOM-INs) of the dorsomedial prefrontal cortex (dmPFC) by an adeno-associated virus vector (AAV) weakens the presynaptic GABAb receptor-mediated suppression of GABA release.

neuroscience↗