ID 111986
Title Alternative
Triphenyltin and glycinergic transmission
Author
Noma, Kazuki Kumamoto University
Akaike, Hironari Kumamoto University
Kurauchi, Yuki Kumamoto University
Katsuki, Hiroshi Kumamoto University
Akaike, Norio Kumamoto University|Kumamoto Kinoh Hospital|Kitamoto Hospital
Keywords
Triphenyltin
Environmental pollution
Spinal neuron
Synaptic bouton preparation
Glycinergic transmission
Glycine
Neuronal transmission
Postsynaptic current
Content Type
Journal Article
Description
Glycine is a fast inhibitory transmitter like γ-aminobutyric acid in the mammalian spinal cord and brainstem, and it is involved in motor reflex, nociception, and neuronal development. Triphenyltin (TPT) is an organometallic compound causing environmental hazard to many wild creatures. Our previous findings show that TPT ultimately induces a drain and/or exhaustion of glutamate in excitatory presynaptic nerve terminals, resulted in blockage of neurotransmission as well as methylmercury. Therefore, we have investigated the neurotoxic mechanism how TPT modulates inhibitory glycinergic transmission in the synaptic bouton preparation of rat isolated spinal neurons using a patch clamp technique. TPT at environmentally relevant concentrations (3–300 nM) significantly increased the number of frequency of glycinergic spontaneous and miniature inhibitory postsynaptic currents (sIPSC and mIPSC) without affecting the current amplitude and decay time. The TPT effects were also observed in external Ca2+-free solution containing tetrodotoxin (TTX) but removed in Ca2+-free solution with both TTX and BAPTA-AM (Ca2+ chelator). On the other hand, the amplitude of glycinergic evoked inhibitory postsynaptic currents (eIPSCs) increased with decreasing failure rate (Rf) and paired pulse ratio (PPR) in the presence of 300 nM TPT. At a high concentration (1 μM), TPT completely blocked eIPSCs after a transient facilitation. Overall, these results suggest that TPT directly acts transmitter-releasing machinery in glycinergic nerve terminals. Effects of TPT on the nerve terminals releasing fast transmitters were greater in the order of glycinergic > glutamatergic > GABAergic ones. Thus, TPT is supposed to cause a strong synaptic modulations on glycinergic neurotransmission in wild creatures.
Journal Title
Environmental Research
ISSN
00139351
NCID
AA12311499
AA11532415
Publisher
Elsevier
Volume
163
Start Page
186
End Page
193
Published Date
2018-02-22
Remark
論文本文は2020-02-24公開予定
Rights
© 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
EDB ID
DOI (Published Version)
URL ( Publisher's Version )
language
eng
TextVersion
その他
departments
Bioscience and Bioindustry