Cardiac Inotropy and Ca Overload

  • Donald M. Bers
Part of the Developments in Cardiovascular Medicine book series (DICM, volume 122)


My aim in this chapter is to discuss some of the general mechanisms involved in cardiac inotropy and their relationship with cellular Ca overload. I do not plan to provide a comprehensive review of either inotropic agents or cardiac pathophysiology. I will start by considering four fundamentally different examples of cardiac inotropy: 1) β-adrenergic activation, 2) α-adrenergic activation, 3) hypothermia and 3) cardioactive steroids (digitalis glycosides). Then I will discuss the ways in which intracellular Ca metabolism can go awry, with particular emphasis on Ca overload. Finally, I will address strategic sites for induction of cardiac inotropy. These discussions may help to bring some of the characteristics of specific cellular systems discussed in preceding chapters into a more integrative picture of cellular Ca regulation.


Adrenergic Agonist Rabbit Ventricle Increase Action Potential Duration Cardioactive Steroid Rabbit Ventricular Muscle 
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Copyright information

© Springer Science+Business Media Dordrecht 1993

Authors and Affiliations

  • Donald M. Bers
    • 1
  1. 1.Department of PhysiologyLoyola University Medical SchoolMaywoodUSA

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