000646749 001__ 646749 000646749 005__ 20260317211508.0 000646749 0247_ $$2doi$$a10.3389/fcvm.2026.1753083 000646749 0247_ $$2datacite_doi$$a10.3204/PUBDB-2026-00948 000646749 037__ $$aPUBDB-2026-00948 000646749 041__ $$aEnglish 000646749 082__ $$a610 000646749 1001_ $$0P:(DE-H253)PIP1014681$$aLi, Mei$$b0 000646749 245__ $$aEffects of cooling on pig heart excitation and contraction 000646749 260__ $$aLausanne$$bFrontiers Media$$c2026 000646749 3367_ $$2DRIVER$$aarticle 000646749 3367_ $$2DataCite$$aOutput Types/Journal article 000646749 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article$$bjournal$$mjournal$$s1773753668_2931546 000646749 3367_ $$2BibTeX$$aARTICLE 000646749 3367_ $$2ORCID$$aJOURNAL_ARTICLE 000646749 3367_ $$00$$2EndNote$$aJournal Article 000646749 520__ $$aAlthough variations in temperature have a profound impact on cardiac function, little is known regarding the excitation and contractile parameters over a broad temperature interval. In view of the clinical applications of lowered temperature in resuscitation and in cardiac preservation/evaluation for transplantation, we have examined the contractile function using Langendorff perfused hearts and isolated trabecular muscle from pig, in combination with electrophysiology and X-ray diffraction. Lowered temperature in the range 37 to 22oC was associated with an increase in systolic pressure and active force. In permeabilized preparations, force and Ca2+ sensitivity decreased with temperature, showing that the increased force down to 22oC in the intact heart and trabeculae was not due to changes in thin filament regulation, but most likely to increased activator [Ca2+]. At lower temperature (<22oC), force in the heart decreased, suggesting that the temperature effects in the regulatory system became dominating. ECG analysis showed that frequency was lowered and that PQ-, QS- and QT- times were prolonged at lower temperature. This was associated with a gradual depolarization of the cell membrane, prolonged action potential and an attenuation of the fast upstroke phase. These changes in rise time and amplitude of the action potential would predispose for uneven propagation and arrhythmia as temperature is lowered. At the same time, the prolonged action potential can be associated with an increased [Ca2+] at lower temperature. Small angle X-ray diffraction showed that the filament lattice of intact trabecular muscle tended to swell at low temperature (10 vs 22oC) and revealed a mass transfer from myosin to actin filaments, which would reflect changes in cellular physiology and contractile system structure at low temperature 000646749 536__ $$0G:(DE-HGF)POF4-633$$a633 - Life Sciences – Building Blocks of Life: Structure and Function (POF4-633)$$cPOF4-633$$fPOF IV$$x0 000646749 536__ $$0G:(DE-HGF)POF4-6G3$$a6G3 - PETRA III (DESY) (POF4-6G3)$$cPOF4-6G3$$fPOF IV$$x1 000646749 536__ $$0G:(DE-HGF)2020_Join2-SWEDEN-DESY$$aSWEDEN-DESY - SWEDEN-DESY Collaboration (2020_Join2-SWEDEN-DESY)$$c2020_Join2-SWEDEN-DESY$$x2 000646749 588__ $$aDataset connected to CrossRef, Journals: bib-pubdb1.desy.de 000646749 693__ $$0EXP:(DE-H253)P-P03-20150101$$1EXP:(DE-H253)PETRAIII-20150101$$6EXP:(DE-H253)P-P03-20150101$$aPETRA III$$fPETRA Beamline P03$$x0 000646749 7001_ $$0P:(DE-H253)PIP1092230$$aPersson, Linus B.$$b1$$eCorresponding author 000646749 7001_ $$0P:(DE-H253)PIP1010504$$aSchwartzkopf, Matthias$$b2 000646749 7001_ $$aSteen, Erik$$b3 000646749 7001_ $$0P:(DE-H253)PIP1027272$$aTerry, Ann$$b4 000646749 7001_ $$0P:(DE-H253)PIP1032321$$aWohlfart, Björn$$b5 000646749 7001_ $$0P:(DE-HGF)0$$aSteen, Stig$$b6$$eCorresponding author 000646749 7001_ $$0P:(DE-H253)PIP1008039$$aArner, Anders$$b7$$eCorresponding author 000646749 773__ $$0PERI:(DE-600)2781496-8$$a10.3389/fcvm.2026.1753083$$gVol. 13, p. 1753083$$p1753083$$tFrontiers in Cardiovascular Medicine$$v13$$x2297-055X$$y2026 000646749 8564_ $$uhttps://bib-pubdb1.desy.de/record/646749/files/Temperaturepaper.pdf$$yOpenAccess 000646749 8564_ $$uhttps://bib-pubdb1.desy.de/record/646749/files/Temperaturepaper.pdf?subformat=pdfa$$xpdfa$$yOpenAccess 000646749 909CO $$ooai:bib-pubdb1.desy.de:646749$$popenaire$$popen_access$$pVDB$$pdriver$$pdnbdelivery 000646749 9101_ $$0I:(DE-HGF)0$$6P:(DE-H253)PIP1014681$$aExternal Institute$$b0$$kExtern 000646749 9101_ $$0I:(DE-HGF)0$$6P:(DE-H253)PIP1092230$$aExternal Institute$$b1$$kExtern 000646749 9101_ $$0I:(DE-588b)2008985-5$$6P:(DE-H253)PIP1010504$$aDeutsches Elektronen-Synchrotron$$b2$$kDESY 000646749 9101_ $$0I:(DE-HGF)0$$6P:(DE-H253)PIP1027272$$aExternal Institute$$b4$$kExtern 000646749 9101_ $$0I:(DE-HGF)0$$6P:(DE-H253)PIP1032321$$aExternal Institute$$b5$$kExtern 000646749 9101_ $$0I:(DE-HGF)0$$6P:(DE-H253)PIP1008039$$aExternal Institute$$b7$$kExtern 000646749 9131_ $$0G:(DE-HGF)POF4-633$$1G:(DE-HGF)POF4-630$$2G:(DE-HGF)POF4-600$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$aDE-HGF$$bForschungsbereich Materie$$lVon Materie zu Materialien und Leben$$vLife Sciences – Building Blocks of Life: Structure and Function$$x0 000646749 9131_ $$0G:(DE-HGF)POF4-6G3$$1G:(DE-HGF)POF4-6G0$$2G:(DE-HGF)POF4-600$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$aDE-HGF$$bForschungsbereich Materie$$lGroßgeräte: Materie$$vPETRA III (DESY)$$x1 000646749 9141_ $$y2026 000646749 915__ $$0StatID:(DE-HGF)0200$$2StatID$$aDBCoverage$$bSCOPUS$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0160$$2StatID$$aDBCoverage$$bEssential Science Indicators$$d2024-12-28 000646749 915__ $$0LIC:(DE-HGF)CCBY4$$2HGFVOC$$aCreative Commons Attribution CC BY 4.0 000646749 915__ $$0StatID:(DE-HGF)0100$$2StatID$$aJCR$$bFRONT CARDIOVASC MED : 2022$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0501$$2StatID$$aDBCoverage$$bDOAJ Seal$$d2023-11-08T21:39:58Z 000646749 915__ $$0StatID:(DE-HGF)0500$$2StatID$$aDBCoverage$$bDOAJ$$d2023-11-08T21:39:58Z 000646749 915__ $$0StatID:(DE-HGF)0113$$2StatID$$aWoS$$bScience Citation Index Expanded$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0700$$2StatID$$aFees$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0150$$2StatID$$aDBCoverage$$bWeb of Science Core Collection$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)9900$$2StatID$$aIF < 5$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0510$$2StatID$$aOpenAccess 000646749 915__ $$0StatID:(DE-HGF)0030$$2StatID$$aPeer Review$$bDOAJ : Anonymous peer review$$d2023-11-08T21:39:58Z 000646749 915__ $$0StatID:(DE-HGF)0561$$2StatID$$aArticle Processing Charges$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0300$$2StatID$$aDBCoverage$$bMedline$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)1110$$2StatID$$aDBCoverage$$bCurrent Contents - Clinical Medicine$$d2024-12-28 000646749 915__ $$0StatID:(DE-HGF)0199$$2StatID$$aDBCoverage$$bClarivate Analytics Master Journal List$$d2024-12-28 000646749 9201_ $$0I:(DE-H253)FS_DOOR-User-20241023$$kFS DOOR-User$$lFS DOOR-User$$x0 000646749 9201_ $$0I:(DE-H253)FS-PET-D-20190712$$kFS-PET-D$$lExperimentebetreuung PETRA III$$x1 000646749 980__ $$ajournal 000646749 980__ $$aVDB 000646749 980__ $$aUNRESTRICTED 000646749 980__ $$aI:(DE-H253)FS_DOOR-User-20241023 000646749 980__ $$aI:(DE-H253)FS-PET-D-20190712 000646749 9801_ $$aFullTexts