Evidence map›Paper›PMID 21301131›Full record

ArticleCirculation journal : official journal of the Japanese Circulation Society2011

Intracellular calcium and the mechanism of anodal supernormal excitability in langendorff perfused rabbit ventricles.

Boyoung Joung, Hyung-Wook Park, Mitsunori Maruyama, Liang Tang, Juan Song, Seongwook Han, Gianfranco Piccirillo, James N Weiss, Shien-Fong Lin, Peng-Sheng Chen

Open access · bronzeAbstract read
In one paragraph

Article in Circulation journal : official journal of the Japanese Circulation Society, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
1.6field-weighted citation impact, top 16% 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

4 citing papers in PubMed, 13 citations in OpenAlex.

  1. Review
  2. Article
  3. Intracellular calcium and the mechanism of the dip in the anodal strength-interval curve in cardiac tissue.Circulation journal : official journal of the Japanese Circulation Society · 2014
    Article
  4. The strength-interval curve in cardiac tissue.Computational and mathematical methods in medicine · 2013
    Review
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

10 authors at 3 institutions in 1 country.

Boyoung JoungKrannert Institute of Cardiology and the Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Hyung-Wook Park
Mitsunori Maruyama
Liang Tang
Juan Song
Seongwook Han
Gianfranco Piccirillo
James N Weiss
Shien-Fong Lin
Peng-Sheng Chen
Indiana University School of MedicineIndiana University · USUniversity of California, Los Angeles · US

Funding

WAVE DYNAMICS IN NORMAL AND DISEASED RABBIT HEARTSP01HL078931 · NHLBI · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI WEISS, JAMES · 2005 to 2015
$20.7M
Thoracic Veins and Sustained Atrial FibrillationR01HL071140 · NHLBI · INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS · PI CHEN, PENG-SHENG · 2002 to 2014
$4.7M
Fibrillation and DefibrillationR01HL078932 · NHLBI · TRUSTEES OF INDIANA UNIVERSITY · PI CHEN, PENG-SHENG · 2005 to 2010
$2.3M
NHLBI NIH HHS P01 HL078931NHLBI NIH HHS P01 HL78931NHLBI NIH HHS R01 HL071140NHLBI NIH HHS R01 HL078932NHLBI NIH HHS R01 HL71140NHLBI NIH HHS R01 HL78932
6 · The paper itself

Abstract

backgroundAnodal stimulation hyperpolarizes the cell membrane and increases the intracellular Ca(2+) (Ca(i)) transient. This study tested the hypothesis that the maximum slope of the Ca(i) decline (-(dCa(i)/dt)(max)) corresponds to the timing of anodal dip on the strength-interval curve and the initiation of repetitive responses and ventricular fibrillation (VF) after a premature stimulus (S(2)). METHODS AND

resultsWe simultaneously mapped the membrane potential (V(m)) and Ca(i) in 23 rabbit ventricles. A dip in the anodal strength-interval curve was observed. During the anodal dip, ventricles were captured by anodal break excitation directly under the S(2) electrode. The Ca(i) following anodal stimuli is larger than that following cathodal stimuli. The S(1)-S(2) intervals of the anodal dip (203±10 ms) coincided with the -(dCa(i)/dt)(max) (199±10 ms, P=NS). BAPTA-AM (n=3), inhibition of the electrogenic Na(+)-Ca(2+) exchanger current (I(NCX)) by low extracellular Na(+) (n=3), and combined ryanodine and thapsigargin infusion (n=2) eliminated the anodal supernormality. Strong S(2) during the relative refractory period (n=5) induced 29 repetitive responses and 10 VF episodes. The interval between S(2) and the first non-driven beat was coincidental with the time of -(dCa(i)/dt)(max).

conclusionsLarger Ca(i) transient and I(NCX) activation induced by anodal stimulation produces anodal supernormality. The time of maximum I(NCX) activation is coincidental to the induction of non-driven beats from the Ca(i) sinkhole after a strong premature stimulation.

Indexed as

Membrane PotentialsAnimalsCalciumElectric StimulationElectrodesHeart VentriclesPerfusionRabbitsCalcium

Identifiers

PMID21301131
PMCPMC3366464
OpenAlexW1976860051

What OpenQuestion holds

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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.