Affordable Access

Publisher Website

Isolation of rat cardiac sarcoplasmic reticulum with improved Ca2+uptake and ryanodine binding

Journal of Molecular and Cellular Cardiology
Publication Date
DOI: 10.1016/0022-2828(91)90061-p
  • Sarcoplasmic Reticulum
  • Rat
  • Ryanodine
  • Ca2+Uptake
  • Ruthenium Red


Abstract The instability of the oxalate-supported Ca 2+ uptake activity of rat cardiac sarcoplasmic reticulum (CSR) in ventricular homogenates most likely accounts for the low specific activity of the rate of oxalate-supported Ca 2+ uptake in previously reported fractions of isolated rat CSR. We have found that CSR vesicles with improved Ca 2+ transport capabilities can be isolated if 1 m KCl is used to stabilize the CSR activity and to allow the extraction of the CSR from the cellular debris. The average rate of Ca 2+ uptake by the isolated rat CSR in the presence of 10 m m oxalate at 37°C was 0.45 μmol/min-mg in the absence of CSR Ca 2+ channel blockers and 0.87 μmol/min-mg in the presence of 10 μ m ruthenium red. The Ca 2+-dependent ATPase activity under the conditions of oxlate-supported uptake was 1.25 μmol/min-mg and 0.84 μmol/min-mg in the absence and presence of 10 μ m ruthenium red, respectively. The rat CSR vesicles bound 3H-ryanodine with a K d of 1.45 n m and a B max of 3.7 pmol/mg. The level of phosphorylated intermediate was 0.30 nmol/mg. The values of B max, EP and Ca 2+-ATPase activity are from one-third to one-half of those previously reported for isolated canine CSR vesicles. These results suggest that the isolated rat CSR may be quite similar to dog CSR.

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times

More articles like this

Isolation of rat cardiac sarcoplasmic reticulum wi...

on Journal of molecular and cellu... March 1991

Effect of ischemia and ischemia--reperfusion on ry...

on Journal of molecular and cellu... September 1995

Effect of ischemia and ischemia-reperfusion on rya...

on Journal of Molecular and Cellu... Jan 01, 1995

[Comparison of ryanodine binding to cardiac sarcop...

on Zhongguo ying yong sheng li xu... February 2002
More articles like this..