Related Experiment Video
Updated: Jul 15, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
Published on: July 3, 2013
Bradykinin induced sustained anti-adrenergic actions in guinea pig heart muscle involves PKC
Laila Arvola1, Geir Bertelsen, Kirsti Ytrehus
1Kirkenes Hospital, Kirkenes, and Department of Medical Physiology, Faculty of Medicine, University of Tromsø, Norway.
Objectives:
Adenosine attenuates the effect of beta-adrenergic stimulation upon contractile force, both when present during beta-adrenergic stimulation and for a period after washout of adenosine. Protein kinase C (PKC) mediates the sustained effect. The present study investigated if bradykinin (500 nM) could induce anti-beta-adrenergic actions.
Design:
Guinea pig papillary muscles (36.5 degrees C, 1 Hz) were subjected to 15 min exposure to and 20 min washout of bradykinin. Isoproterenol 100 nM was added for 3 min at the end of test exposure and at the end of washout. The PKC-inhibitor bisindolylmaleimide (20 nM) was given to investigate the importance of PKC.
Results:
Bradykinin significantly reduced the increase in contractile force in response to isoproterenol, both when present and after washout of test substance. Inhibition of PKC abolished the sustained effect, while inhibition of PI3-kinase with wortmannin did not seem to affect the results.
Conclusions:
Anti-beta-adrenergic effects of bradykinin on contractile force and action potential duration were demonstrated. PKC was important for the sustained effect on contractile force, but not for the acute effect and the effect on action potential duration.
Related Concept Videos
Adrenergic Receptors: β Subtype
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
cAMP-dependent Protein Kinase Pathways
G-Protein Gated Ion Channels
Sensory organs,...
GPCRs Regulate Adenylyl Cylase Activity
Two...
Adrenergic Receptors: ɑ Subtype
Adrenaline ≥ Noradrenaline >> Isoprenaline
α-adrenoceptors are further divided into α1 and α2-adrenoceptors.
α1-Adrenoceptors: These receptors are located postsynaptically on the effector organs and cause constriction of smooth muscle mediated by activation of phospholipase C—inositol-1,4,5-trisphosphate...
Heart Failure Drugs: Inhibitors of Renin-Angiotensin System
