Abstract
"Postextrasystolic potentiation" of isotonic contractions of the intact isolated rat heart was studied. It was found that the Frank-Starling mechanism does not participate in the increase of the contraction following a premature beat and a compensatory pause. A linear relationship could be demonstrated between the prematurity of the extra beat and the amplitude of the postcompensatory contraction. The increase of amplitude of the postcompensatory contraction was found to counterbalance the decrease of the premature beat. At a constant net rate, whether the rhythm was regular or not, the average contraction height was constant. Postextrasystolic potentiation pattern following an interpolating premature beat was different from postextrasystolic potentiation following a premature beat and a compensatory pause. Postextrasystolic potentiation following an interpolating premature beat could not be distinguished from poststimulation potentiation. It was therefore concluded that postextrasystolic potentiation does not exist as a specific phenomenon.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
