RRC ID 57681
著者 Ikeda K, Igarashi H, Yawo H, Kobayashi K, Arata S, Kawakami K, Izumizaki M, Onimaru H.
タイトル Optogenetic analysis of respiratory neuronal networks in the ventral medulla of neonatal rats producing channelrhodopsin in Phox2b-positive cells.
ジャーナル Pflugers Arch
Abstract Paired-like homeobox gene Phox2b is predominantly expressed in pre-inspiratory neurons in the parafacial respiratory group (pFRG) in newborn rat rostral ventrolateral medulla. To analyse detailed local networks of the respiratory centre using optogenetics, the effects of selective activation of Phox2b-positive neurons in the ventral medulla on respiratory rhythm generation were examined in brainstem-spinal cord preparations isolated from transgenic newborn rats with Phox2b-positive cells expressing channelrhodopsin variant ChRFR(C167A). Photostimulation up to 43 s increased the respiratory rate > 200% of control, whereas short photostimulation (1.5 s) of the rostral pFRG reset the respiratory rhythm. At the cellular level, photostimulation depolarised Phox2b-positive pre-inspiratory, inspiratory and respiratory-modulated tonic neurons and Phox2b-negative pre-inspiratory neurons. In contrast, changes in membrane potential of Phox2b-negative inspiratory and expiratory neurons varied depending on characteristics of ongoing synaptic connections in local respiratory networks in the rostral medulla. In the presence of tetrodotoxin, photostimulation depolarised Phox2b-positive cells, but caused no significant changes in membrane potential of Phox2b-negative cells. We concluded that depolarisation of Phox2b-positive neurons was due to cell-autonomous photo-activation and summation of excitatory postsynaptic potentials, whereas membrane potential changes of Phox2b-negative neurons depended on the network configuration. Our findings shed further light on local networks among respiratory-related neurons in the rostral ventrolateral medulla and emphasise the important role of pre-inspiratory neurons in respiratory rhythm generation in the neonatal rat en bloc preparation.
巻・号 471(11-12)
ページ 1419-1439
公開日 2019-12-1
DOI 10.1007/s00424-019-02317-9
PII 10.1007/s00424-019-02317-9
PMID 31631251
MeSH Animals Animals, Newborn Brain Stem / metabolism Channelrhodopsins / metabolism* Female Homeodomain Proteins / metabolism* Male Medulla Oblongata / metabolism* Membrane Potentials / physiology Neurons / metabolism* Optogenetics / methods Rats Respiration Respiratory Center / metabolism* Tetrodotoxin / metabolism Transcription Factors / metabolism*
IF 3.158
引用数 1
リソース情報
ラット LE-Tg(Gt(ROSA)26Sor-CAG-COP4*C167A/YFP*)1Jfhy (strainID=1237)