All three ryanodine receptor isoforms generate rapid cooling responses in muscle cells

Feliciano Protasi, Alexander Shtifman, Fred J. Julian, Paul D. Allen

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


The rapid cooling (RC) response in muscle is an increase in cytoplasmic Ca2+ concentration ([Ca2+]i) that is probably caused by Ca2+ release from the sarcoplasmic reticulum (SR). However, the molecular bases of this response have not been completely elucidated. Three different isoforms of the SR Ca2+ release channels, or ryanodine receptors (RyRs), have been isolated (RyR1, RyR2, and RyR3). In the current investigation, the RC response was studied in RyR-null muscle cells (1B5) before and after transduction with HSV-1 virions containing the cDNAs encoding for RyR1, RyR2, or RyR3. Cells were loaded with fluo 4-AM to monitor changes in [Ca2+]i and perfused with either cold (∼0°C), room temperature (RT), or RT buffer containing 40 mM caffeine. Control cells showed no significant response to cold or caffeine, whereas robust Ca2+ transients were recorded in response to both RC and caffeine in transduced cells expressing any one of the three RyR isoforms. Our data demonstrate directly that RyRs are responsible for the RC response and that all three isoforms respond in a similar manner. Ca2+ release from RyRs is likely caused by a RC-induced conformational change of the channel from the closed to the open state.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Cell Physiology
Issue number3 55-3
StatePublished - Mar 2004
Externally publishedYes


  • Calcium release channel
  • Excitation-contraction coupling
  • Sarcoplasmic reticulum

ASJC Scopus subject areas

  • Clinical Biochemistry
  • Cell Biology
  • Physiology


Dive into the research topics of 'All three ryanodine receptor isoforms generate rapid cooling responses in muscle cells'. Together they form a unique fingerprint.

Cite this