The properties of synaptic integration at the local dendrite of auditory coincidence detector neurons.

2016 Fiscal Year Final Research Report

• Project/Area Number: 25460285
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General physiology
• Research Institution: Nagoya University
• Principal Investigator: Yamada Rei 名古屋大学, 医学系研究科, 助教 (70422970)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: 樹状突起 / 同時検出 / シナプス / 音源定位

Outline of Final Research Achievements

Neurons in nucleus laminaris (NL) of birds are the coincidence detector of binaural inputs and involved in processing of interaural time differences (ITDs). NL neurons with low tuning frequency (LF neurons) have prominently longer dendrites than the other frequency neurons have. However, how the dendrites contribute to the ITD processing is not well understood. In this study, we first analyzed the distribution of glutamate receptors along the dendrites with the focal uncaging of glutamate. We found that large currents were generated at distal dendrites of the LF neurons. As the amplitude of mEPSCs was uniform along the dendrites, the synaptic terminals might be concentrated at the distal dendrites. We recorded the voltage at the soma and found that the synaptic inputs on the distal dendrites were strongly attenuated because of the local depolarization and following activation of K+ channels. This attenuation might contribute to the intensity-dependent regulation of ITD processing.

Free Research Field

神経生理学