論文

査読有り
2012年3月

Synthetic localized calcium transients directly probe signalling mechanisms in skeletal muscle

JOURNAL OF PHYSIOLOGY-LONDON
  • Lourdes Figueroa
  • ,
  • Vyacheslav M. Shkryl
  • ,
  • Jingsong Zhou
  • ,
  • Carlo Manno
  • ,
  • Atsuya Momotake
  • ,
  • Gustavo Brum
  • ,
  • Lothar A. Blatter
  • ,
  • Graham C. R. Ellis-Davies
  • ,
  • Eduardo Rios

590
6
開始ページ
1389
終了ページ
1411
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1113/jphysiol.2011.225854
出版者・発行元
WILEY-BLACKWELL

The contribution of Ca2+-induced Ca2+ release (CICR) to trigger muscle contraction is controversial. It was studied on isolated muscle fibres using synthetic localized increases in Ca2+ concentration, SLICs, generated by two-photon photorelease from nitrodibenzofuran (NDBF)-EGTA just outside the permeabilized plasma membrane. SLICs provided a way to increase cytosolic [Ca2+] rapidly and reversibly, up to 8 mu M, levels similar to those reached during physiological activity. They improve over previous paradigms in rate of rise, locality and reproducibility. Use of NDBF-EGTA allowed for the separate modification of resting [Ca2+], trigger [Ca2+] and resting [Mg2+]. In frog muscle, SLICs elicited propagated responses that had the characteristics of CICR. The threshold [Ca2+] for triggering a response was 0.5 mu M or less. As this value is much lower than concentrations prevailing near channels during normal activity, the result supports participation of CICR in the physiological control of contraction in amphibian muscle. As SLICs were applied outside cells, the primary stimulus was Ca2+, rather than the radiation or subproducts of photorelease. Therefore the responses qualify as 'classic' CICR. By contrast, mouse muscle fibres did not respond unless channel-opening drugs were present at substantial concentrations, an observation contrary to the physiological involvement of CICR in mammalian excitation-contraction coupling. In mouse muscle, the propagating wave had a substantially lower release flux, which together with a much higher threshold justified the absence of response when drugs were not present. The differences in flux and threshold may be ascribed to the absence of ryanodine receptor 3 (RyR3) isoforms in adult mammalian muscle.

Web of Science ® 被引用回数 : 19

リンク情報
DOI
https://doi.org/10.1113/jphysiol.2011.225854
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000301491300013&DestApp=WOS_CPL
ID情報
  • DOI : 10.1113/jphysiol.2011.225854
  • ISSN : 0022-3751
  • Web of Science ID : WOS:000301491300013

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