{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T02:38:48Z","timestamp":1777516728545,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,17]],"date-time":"2023-03-17T00:00:00Z","timestamp":1679011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003977","name":"Israel Science Foundation","doi-asserted-by":"publisher","award":["330\/19"],"award-info":[{"award-number":["330\/19"]}],"id":[{"id":"10.13039\/501100003977","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Technion Hiroshi Fujiwara Cyber Security Research Center","award":["330\/19"],"award-info":[{"award-number":["330\/19"]}]},{"name":"Israel Cyber Directorate (Y.Y. and M.D.)","award":["330\/19"],"award-info":[{"award-number":["330\/19"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Bradycardia is initiated by the sinoatrial node (SAN), which is regulated by a coupled-clock system. Due to the clock coupling, reduction in the \u2018funny\u2019 current (If), which affects SAN automaticity, can be compensated, thus preventing severe bradycardia. We hypothesize that this fail-safe system is an inherent feature of SAN pacemaker cells and is driven by synergy between If and other ion channels. This work aimed to characterize the connection between membrane currents and their underlying mechanisms in SAN cells. SAN tissues were isolated from C57BL mice and Ca2+ signaling was measured in pacemaker cells within them. A computational model of SAN cells was used to understand the interactions between cell components. Beat interval (BI) was prolonged by 54 \u00b1 18% (N = 16) and 30 \u00b1 9% (N = 21) in response to If blockade, by ivabradine, or sodium current (INa) blockade, by tetrodotoxin, respectively. Combined drug application had a synergistic effect, manifested by a BI prolonged by 143 \u00b1 25% (N = 18). A prolongation in the local Ca2+ release period, which reports on the level of crosstalk within the coupled-clock system, was measured and correlated with the prolongation in BI. The computational model predicted that INa increases in response to If blockade and that this connection is mediated by changes in T and L-type Ca2+ channels.<\/jats:p>","DOI":"10.3390\/ijms24065786","type":"journal-article","created":{"date-parts":[[2023,3,20]],"date-time":"2023-03-20T04:33:31Z","timestamp":1679286811000},"page":"5786","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Synergy between Membrane Currents Prevents Severe Bradycardia in Mouse Sinoatrial Node Tissue"],"prefix":"10.3390","volume":"24","author":[{"given":"Limor","family":"Arbel Ganon","sequence":"first","affiliation":[{"name":"Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6322-6523","authenticated-orcid":false,"given":"Moran","family":"Davoodi","sequence":"additional","affiliation":[{"name":"Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandra","family":"Alexandrovich","sequence":"additional","affiliation":[{"name":"Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yael","family":"Yaniv","sequence":"additional","affiliation":[{"name":"Laboratory of Bioelectric and Bioenergetic Systems, Faculty of Biomedical Engineering, Technion-IIT, Haifa 3200003, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1001\/jamainternmed.2015.7655","article-title":"Association of asymptomatic bradycardia with incident cardiovascular disease and mortality: The Multi-Ethnic Study of Atherosclerosis (MESA)","volume":"176","author":"Dharod","year":"2016","journal-title":"JAMA Intern. 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