Evidence map›Paper›PMID 12642597›Full record

ArticleThe Journal of general physiology2003

Simulation of calcium sparks in cut skeletal muscle fibers of the frog.

W K Chandler, S Hollingworth, S M Baylor

Abstract readComparative StudyEvaluation StudyValidation Study
PubMed Full text at PMC Publisher
In one paragraph

Article in The Journal of general physiology, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers.

0numbers the graph read from it
0cells of the map it votes in
23citing papers in PubMed
1.6field-weighted citation impact, top 17% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

23 citing papers in PubMed, 32 citations in OpenAlex.

  1. Review
  2. Article
  3. Article
  4. Article
  5. Review
  6. Article
  7. Theory and applications of geometric scaling of localized calcium release events.American journal of physiology. Cell physiology · 2010
    Article
  8. Article
  9. Article
  10. Article
  11. Article
  12. Local PIP(2) signals: when, where, and how?Pflugers Archiv : European journal of physiology · 2007
    Review
  13. Novel approach to real-time flash photolysis and confocal [Ca2+] imaging.Pflugers Archiv : European journal of physiology · 2007
    Article
  14. Article
  15. Depletion "skraps" and dynamic buffering inside the cellular calcium store.Proceedings of the National Academy of Sciences of the United States of America · 2006
    Article
  16. Review
  17. Article
  18. Article
  19. Article
  20. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors at 2 institutions in 1 country.

W K ChandlerDepartment of Cellular and Molecular Physiology, Yale Universtiy School of Medicine, New Haven, CT 06520, USA.
S Hollingworth
S M Baylor
University of Pennsylvania · USYale University · US

Funding

EXCITATION-CONTRACTION COUPLING IN STRIATED MUSCLER01NS017620 · NINDS · UNIVERSITY OF PENNSYLVANIA · PI BAYLOR, STEPHEN M. · 1985 to 2005
$1.9M
NIADDK NIH HHS AM 37643NINDS NIH HHS NS 17620NINDS NIH HHS R01 NS017620
6 · The paper itself

Abstract

Spark mass, the volume integral of Delta F/F, was investigated theoretically and with simulations. These studies show that the amount of Ca2+ bound to fluo-3 is proportional to mass times the total concentration of fluo-3 ([fluo-3T]); the proportionality constant depends on resting Ca2+ concentration ([Ca2+]R). In the simulation of a Ca2+ spark in an intact frog fiber with [fluo-3T] = 100 microM, fluo-3 captures approximately one-fourth of the Ca2+ released from the sarcoplasmic reticulum (SR). Since mass in cut fibers is several times that in intact fibers, both with similar values of [fluo-3T] and [Ca2+]R, it seems likely that SR Ca2+ release is larger in cut fiber sparks or that fluo-3 is able to capture a larger fraction of the released Ca2+ in cut fibers, perhaps because of reduced intrinsic Ca2+ buffering. Computer simulations were used to identify these and other factors that may underlie the differences in mass and other properties of sparks in intact and cut fibers. Our spark model, which successfully simulates calcium sparks in intact fibers, was modified to reflect the conditions of cut fiber measurements. The results show that, if the protein Ca2+-buffering power of myoplasm is the same as that in intact fibers, the Ca2+ source flux underlying a spark in cut fibers is 5-10 times that in intact fibers. Smaller source fluxes are required for less buffer. In the extreme case in which Ca2+ binding to troponin is zero, the source flux needs to be 3-5 times that in intact fibers. An increased Ca2+ source flux could arise from an increase in Ca2+ flux through one ryanodine receptor (RYR) or an increase in the number of active RYRs per spark, or both. These results indicate that the gating of RYRs, or their apparent single channel Ca2+ flux, is different in frog cut fibers--and, perhaps, in other disrupted preparations--than in intact fibers.

Indexed as

Models, BiologicalAnimalsCalciumCalcium SignalingComputer SimulationHindlimbMuscle Fibers, SkeletalMuscle, SkeletalRana pipiensRyanodine Receptor Calcium Release ChannelStochastic ProcessesCalciumRyanodine Receptor Calcium Release Channel

Identifiers

PMID12642597
PMCPMC2217372
OpenAlexW2147462920

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-SA
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.