Evidence map›Paper›PMID 42113868›Full record

ArticlePLoS computational biology2026

A new Fight-or-Flight Pacemaker Mechanism via Ryanodine Receptor abundance and superclustering.

Valeria Ventura Subirachs, Syevda Tagirova, Alexander V Maltsev, Dongmei Yang, Edward G Lakatta, Michael D Stern, Victor A Maltsev

Abstract read
In one paragraph

Article in PLoS computational biology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
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

1 citing paper in PubMed.

  1. 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

7 authors.

Valeria Ventura SubirachsNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.
Syevda TagirovaNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.
Alexander V MaltsevNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.
Dongmei YangNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.
Edward G LakattaNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.
Michael D SternNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.
Victor A MaltsevNational Institute on Aging, NIH, Biomedical Research Center, Baltimore, Maryland, United States of America.ORCID https://orcid.org/0000-0002-3832-791X

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The sinoatrial node is the primary cardiac pacemaker. Individual sinoatrial node cells (SANCs) generate spontaneous rhythmic action potentials (APs) that initiate each heartbeat. The mechanism of SANC automaticity and its modulation by autonomic nervous system is based on the coupled function of molecules of both the cell membrane (ion channels, exchangers, and pumps) and the sarcoplasmic reticulum (SR), which generates rhythmic local Ca releases (LCRs). While LCRs are generated by ryanodine receptors (RyRs), the molecular-scale RyR network structure remains unknown. Here we performed single-molecule localization of RyRs via direct Stochastic Optical Reconstruction Microscopy (dSTORM) in rabbit SANCs in basal conditions and 5 minutes after β-adrenergic receptor (βAR) stimulation by isoproterenol. RyRs form clusters of various sizes, with a mean density of 67.7 ± 13.2 RyR/μm2. (mean±SEM, n = 6 cells). While the majority of cluster sizes ranged from 3 to 32 RyRs, each cell had a few substantially larger clusters (>76 RyRs), dubbed superclusters. βAR stimulation significantly increased the RyR density to 119.1 ± 22.6 RyR/μm2 (8 cells, p ≤ 0.05) and created more superclusters. Our numerical SANC model showed that superclustering substantially decreased the AP cycle length (APCL) by creating Ca release hotspots that initiated larger LCRs under any condition. Increasing RyR density prolonged APCL in the basal state but shortened APCL during βAR stimulation. With no change in RyR network, βAR stimulation of only SR Ca pump and ion currents shortened APCL on average from 414.9 to 284 ms. When realistic higher RyR density and superclustering were added to the model, APCL further shortened to 231.9 ms. Thus, dynamic nanoscale changes in RyR network provide a new powerful pacemaker mechanism.

Indexed as

Biological ClocksRyanodine Receptor Calcium Release ChannelSinoatrial NodeAction PotentialsAnimalsCalciumComputational BiologyIsoproterenolRabbitsSarcoplasmic ReticulumCalciumIsoproterenolRyanodine Receptor Calcium Release Channel

Identifiers

PMID42113868
PMCPMC13178966

What OpenQuestion holds

Textmetadata
LicenceCC0
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.