Evidence map›Paper›PMID 15738048›Full record

ArticleThe Journal of general physiology2005

Phosphorylation of titin modulates passive stiffness of cardiac muscle in a titin isoform-dependent manner.

Norio Fukuda, Yiming Wu, Preetha Nair, Henk L Granzier

Open access · bronzeAbstract read
In one paragraph

Article in The Journal of general physiology, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 97 papers.

0numbers the graph read from it
0cells of the map it votes in
97citing papers in PubMed
7.7field-weighted citation impact, top 2% 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

97 citing papers in PubMed, 198 citations in OpenAlex.

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  13. Molecular regulation of stretch activation.American journal of physiology. Cell physiology · 2022
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  15. Nitric oxide and skeletal muscle contractile function.Nitric oxide : biology and chemistry · 2022
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37 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

4 authors at 1 institution in 1 country.

Norio FukudaDepartment of Veterinary and Comparative Anatomy, Pharmacology and Physiology, Washington State University, Pullman, WA 99164, USA.
Yiming Wu
Preetha Nair
Henk L Granzier
Washington State University · US

Funding

Function of Giant Sarcomere Matrix Proteins in MuscleR01HL062881 · NHLBI · WASHINGTON STATE UNIVERSITY · PI GRANZIER, HENK L. · 1999 to 2018
$6.4M
TITIN AND HEART FUNCTION AND DISEASE (INDIVIDUAL)R01HL061497 · NHLBI · WASHINGTON STATE UNIVERSITY · PI GRANZIER, HENK L. · 1998 to 2007
$3.3M
Titin-based force modulation in cardiac muscleR01HL067274 · NHLBI · WASHINGTON STATE UNIVERSITY · PI GRANZIER, HENK L. · 2001 to 2004
$1.0M
NHLBI NIH HHS HL61497NHLBI NIH HHS HL62881NHLBI NIH HHS HL67274
6 · The paper itself

Abstract

We investigated the effect of protein kinase A (PKA) on passive force in skinned cardiac tissues that express different isoforms of titin, i.e., stiff (N2B) and more compliant (N2BA) titins, at different levels. We used rat ventricular (RV), bovine left ventricular (BLV), and bovine left atrial (BLA) muscles (passive force: RV > BLV > BLA, with the ratio of N2B to N2BA titin, approximately 90:10, approximately 40:60, and approximately 10:90%, respectively) and found that N2B and N2BA isoforms can both be phosphorylated by PKA. Under the relaxed condition, sarcomere length was increased and then held constant for 30 min and the peak passive force, stress-relaxation, and steady-state passive force were determined. Following PKA treatment, passive force was significantly decreased in all muscle types with the effect greatest in RV, lowest in BLA, and intermediate in BLV. Fitting the stress-relaxation data to the sum of three exponential decay functions revealed that PKA blunts the magnitude of stress-relaxation and accelerates its time constants. To investigate whether or not PKA-induced decreases in passive force result from possible alteration of titin-thin filament interaction (e.g., via troponin I phosphorylation), we conducted the same experiments using RV preparations that had been treated with gelsolin to extract thin filaments. PKA decreased passive force in gelsolin-treated RV preparations with a magnitude similar to that observed in control preparations. PKA was also found to decrease restoring force in skinned ventricular myocytes of the rat that had been shortened to below the slack length. Finally, we investigated the effect of the beta-adrenergic receptor agonist isoprenaline on diastolic force in intact rat ventricular trabeculae. We found that isoprenaline phosphorylated titin and that it reduced diastolic force to a degree similar to that found in skinned RV preparations. Taken together, these results suggest that during beta-adrenergic stimulation, PKA increases ventricular compliance in a titin isoform-dependent manner.

Indexed as

Adrenergic beta-AgonistsAnimalsCattleConnectinCyclic AMP-Dependent Protein KinasesElasticityGelsolinIn Vitro TechniquesIsoproterenolMaleMuscle ProteinsMyocardial ContractionPapillary MusclesPhosphorylationProtein IsoformsProtein KinasesAdrenergic beta-AgonistsConnectinCyclic AMP-Dependent Protein KinasesGelsolinIsoproterenolMuscle ProteinsProtein IsoformsProtein Kinases

Identifiers

PMID15738048
PMCPMC2234012
OpenAlexW1980991217

What OpenQuestion holds

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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.