{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T23:17:47Z","timestamp":1787008667451,"version":"build-2736575974"},"reference-count":41,"publisher":"Oxford University Press (OUP)","issue":"17","license":[{"start":{"date-parts":[[2024,9,11]],"date-time":"2024-09-11T00:00:00Z","timestamp":1726012800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000037","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["PJT-178095"],"award-info":[{"award-number":["PJT-178095"]}],"id":[{"id":"10.13039\/501100000037","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000222","name":"Heart and Stroke Foundation of Canada","doi-asserted-by":"publisher","award":["G-16-00013985"],"award-info":[{"award-number":["G-16-00013985"]}],"id":[{"id":"10.13039\/501100000222","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100005266","name":"Women\u2019s Heart Health Initiative of The Molson Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100005266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000156","name":"Fonds de Recherche du Qu\u00e9bec\u2014Sant\u00e9","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100000156","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2024,12,31]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Aims<\/jats:title>\n                    <jats:p>Pregnant (P) women have a significantly elevated resting heart rate (HR), which makes cardiac arrhythmias more likely to occur. Although electrical remodelling of the sinoatrial node (SAN) has been documented, the underlying mechanism is not fully understood. The acetylcholine-activated potassium current (IKACh), one of the major repolarizing currents in the SAN, plays a critical role in HR control by hyperpolarizing the maximal diastolic potential (MDP) of the SAN action potential (AP), thereby reducing SAN automaticity and HR. Thus, considering its essential role in cardiac automaticity, this study aims to determine whether changes in IKACh are potentially involved in the increased HR associated with pregnancy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and results<\/jats:title>\n                    <jats:p>Experiments were conducted on non-pregnant (NP) and pregnant (P; 17\u201318 days gestation) female CD-1 mice aged 2 to 4 months. IKACh was recorded on spontaneously beating SAN cells using the muscarinic agonist carbachol (CCh). Voltage-clamp data showed a reduction in IKACh density during pregnancy, which returned to control values shortly after delivery. The reduction in IKACh was explained by a decrease in protein expression of Kir3.1 channel subunit and the muscarinic type 2 receptor. In agreement with these findings, current-clamp data showed that the MDP of SAN cells from P mice were less hyperpolarized following CCh administration. Surface electrocardiograms (ECGs) recorded on anaesthetized mice revealed that the cholinergic antagonist atropine and the selective KACh channel blocker tertiapin-Q increased HR in NP mice and had only a minimal effect on P mice. AP and ECG data also showed that pregnancy is associated with a decrease in beating and HR variability, respectively.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>IKACh function and expression are decreased in the mouse SAN during pregnancy, strongly suggesting that, in addition to other electrical remodelling of the SAN, reduced IKACh also plays an important role in the pregnancy-induced increased HR.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/cvr\/cvae200","type":"journal-article","created":{"date-parts":[[2024,9,9]],"date-time":"2024-09-09T15:55:00Z","timestamp":1725897300000},"page":"2208-2219","source":"Crossref","is-referenced-by-count":3,"title":["Cardiac automaticity is modulated by IKACh in sinoatrial node during pregnancy"],"prefix":"10.1093","volume":"120","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5757-748X","authenticated-orcid":false,"given":"Val\u00e9rie","family":"Long","sequence":"first","affiliation":[{"name":"Research Center, Montreal Heart Institute , 5000 B\u00e9langer, Montr\u00e9al, Qu\u00e9bec , H1T 1C8","place":["Canada"]},{"name":"Faculty of Pharmacy, Universit\u00e9 de Montr\u00e9al , 2940 Chemin de Polytechnique, Montr\u00e9al, Qu\u00e9bec , H3T 1J4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gracia","family":"El Gebeily","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute , 5000 B\u00e9langer, Montr\u00e9al, Qu\u00e9bec , H1T 1C8","place":["Canada"]},{"name":"Faculty of Pharmacy, Universit\u00e9 de Montr\u00e9al , 2940 Chemin de Polytechnique, Montr\u00e9al, Qu\u00e9bec , H3T 1J4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u00c9lisabeth","family":"Leblanc","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute , 5000 B\u00e9langer, Montr\u00e9al, Qu\u00e9bec , H1T 1C8","place":["Canada"]},{"name":"Faculty of Pharmacy, Universit\u00e9 de Montr\u00e9al , 2940 Chemin de Polytechnique, Montr\u00e9al, Qu\u00e9bec , H3T 1J4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marwa","family":"Senhadji","sequence":"additional","affiliation":[{"name":"Research Center, Montreal Heart Institute , 5000 B\u00e9langer, Montr\u00e9al, Qu\u00e9bec , H1T 1C8","place":["Canada"]},{"name":"Faculty of Pharmacy, Universit\u00e9 de Montr\u00e9al , 2940 Chemin de Polytechnique, Montr\u00e9al, Qu\u00e9bec , H3T 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