Contractility measurements on isolated papillary muscles for the investigation of cardiac inotropy in mice

• Verfasst von: Uhl, Sebastian [VerfasserIn]
• Verfasst von: Freichel, Marc [VerfasserIn]
• Verfasst von: Mathar, Ilka [VerfasserIn]
• Titel: Contractility measurements on isolated papillary muscles for the investigation of cardiac inotropy in mice
• Verf.angabe: Sebastian Uhl, Marc Freichel, Ilka Mathar
• E-Jahr: 2015
• Jahr: September 17, 2015
• Umfang: 1 Online-Ressource (1 Videodatei, 6:22 min)
• Umfang: 10 S.
• Illustrationen: farbig
• Fussnoten: Gesehen am 07.07.2020 ; Enthält auch Textversion ; Wissenschaftlicher Film. Deutschland. 2015
• Titel Quelle: Enthalten in: JoVE. Video journal
• Ort Quelle: [S.l.] : [s.n.], 2006
• Jahr Quelle: 2015
• Band/Heft Quelle: (2015,103) Artikel-Nummer e53076, 10 Seiten
• ISSN Quelle: 1940-087X
• DOI: doi:10.3791/53076
• Datenträger: Online-Ressource
• Dokumenttyp: Film
• Sprache: eng
• K10plus-PPN: 1703804570

Abstract

Papillary muscle isolated from adult mouse hearts can be used to study cardiac contractility during different physiological/pathological conditions. The contractile characteristics can be evaluated independently of external influences such as vascular tonus or neurohumoral status. It depicts a scientific approach between single cell measurements with isolated cardiac myocytes and in vivo studies like echocardiography. Thus, papillary muscle preparations serve as an excellent model to study cardiac physiology/pathophysiology and can be used for investigations like the modulation by pharmacological agents or the exploration of transgenic animal models. Here, we describe a method of isolating the murine left anterior papillary muscle to investigate cardiac contractility in an organ bath setup. In contrast to a muscle strip preparation isolated from the ventricular wall, the papillary muscle can be prepared in toto without damaging the muscle tissue severely. The organ bath setup consists of several temperature-controlled, gassed and electrode-equipped organ bath chambers. The isolated papillary muscle is fixed in the organ bath chamber and electrically stimulated. The evoked twitch force is recorded using a pressure transducer and parameters such as twitch force amplitude and twitch kinetics are analyzed. Different experimental protocols can be performed to investigate the calcium- and frequency-dependent contractility as well as dose-response curves of contractile agents such as catecholamines or other pharmaceuticals. Additionally, pathologic conditions like acute ischemia can be simulated.