Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Caffeine alters cardiac myofilament activity and regulation independently of Ca2+ binding to troponin C

Caffeine alters cardiac myofilament activity and regulation independently of Ca2+ binding to... of Illinois at Chicago, Chicago, Illinois Powers, Frances M., R. John Solaro. cardiac independently of Ca2+ binding to troponin C. Am. J. PhysioZ. 268 (CeZZ Physiol. 37): C1348-C1353, 1995.-We investigated the mechanism by which influences responsiveness to Ca 2+ by measuring isometric force, Ca2+ binding, ATPase of dog cardiac proteins. (20 mM) increased submaximal depressed maximal force in skinned fiber bundles. Although the Ca2+ sensitivity of was increased by , there was no effect on Ca2+ binding to troponin C (TnC) in skinned fiber bundles. To determine if altered actin-myosin interaction or affected myosin directly, myofibrillar, actomyosin, myosin ATPase activities were measured. Maximal Ca2+activated myofibrillar Mg 2+-ATPase was depressed by 20 mM , whereas submaximal Mg2+-ATPase activities were not changed. Actomyosin Mg2+-ATPase was significantly depressed by concentrations > 15 mM. Myosin Ca 2+-ATPase was depressed by , whereas Mg 2+-ATPase K(EDTA)-ATPase activities were not affected. These data suggest that affects function via a mechanism that is independent of TnCCa2+ binding but that may involve direct effects on actin-crossbridge interaction. calcium sensitivity; myosin adenosinetriphosphatase; sin adenosinetriphosphatase; skinned fiber bundles actomyo- 1,3,7-trimethylxanthine, a pharmacological tool commonly used to release Ca2+ from the sarcoplasmic reticulum (SR) in studies of different aspects http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png AJP - Cell Physiology The American Physiological Society

Caffeine alters cardiac myofilament activity and regulation independently of Ca2+ binding to troponin C

AJP - Cell Physiology , Volume 268: C1348 – Jun 1, 1995

Loading next page...
 
/lp/the-american-physiological-society/caffeine-alters-cardiac-myofilament-activity-and-regulation-zvOx8Hnz0d

References

References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.

Publisher
The American Physiological Society
Copyright
Copyright © 1995 the American Physiological Society
ISSN
0363-6143
eISSN
1522-1563
Publisher site
See Article on Publisher Site

Abstract

of Illinois at Chicago, Chicago, Illinois Powers, Frances M., R. John Solaro. cardiac independently of Ca2+ binding to troponin C. Am. J. PhysioZ. 268 (CeZZ Physiol. 37): C1348-C1353, 1995.-We investigated the mechanism by which influences responsiveness to Ca 2+ by measuring isometric force, Ca2+ binding, ATPase of dog cardiac proteins. (20 mM) increased submaximal depressed maximal force in skinned fiber bundles. Although the Ca2+ sensitivity of was increased by , there was no effect on Ca2+ binding to troponin C (TnC) in skinned fiber bundles. To determine if altered actin-myosin interaction or affected myosin directly, myofibrillar, actomyosin, myosin ATPase activities were measured. Maximal Ca2+activated myofibrillar Mg 2+-ATPase was depressed by 20 mM , whereas submaximal Mg2+-ATPase activities were not changed. Actomyosin Mg2+-ATPase was significantly depressed by concentrations > 15 mM. Myosin Ca 2+-ATPase was depressed by , whereas Mg 2+-ATPase K(EDTA)-ATPase activities were not affected. These data suggest that affects function via a mechanism that is independent of TnCCa2+ binding but that may involve direct effects on actin-crossbridge interaction. calcium sensitivity; myosin adenosinetriphosphatase; sin adenosinetriphosphatase; skinned fiber bundles actomyo- 1,3,7-trimethylxanthine, a pharmacological tool commonly used to release Ca2+ from the sarcoplasmic reticulum (SR) in studies of different aspects

Journal

AJP - Cell PhysiologyThe American Physiological Society

Published: Jun 1, 1995

There are no references for this article.