Related Experiment Video
Updated: Sep 23, 2026

Assessment of Cardiac Function and Energetics in Isolated Mouse Hearts Using 31P NMR Spectroscopy
Published on: September 1, 2010
Insensitivity of cardiac phosphofructokinase to adrenergic activation in Zucker rats. A post-receptor defect
Abstract:
The apparent insensitivity of phosphofructokinase to activation by adrenaline in hearts from genetically obese Zucker (fa/fa) rats [Patten, Filsell & Clark (1982) Metab. Clin. Exp. 31, 1137-1141] was examined in detail. Perfusion of hearts from obese (fa/fa) animals with medium containing 1nM-100 microM-adrenaline for 4 min did not significantly activate phosphofructokinase, but fully activated glycogen phosphorylase. Activation of phosphofructokinase occurred in hearts from lean (Fa/?) animals, with half-maximal activation at 10nM-adrenaline. Binding characteristics of cardiac alpha 1-adrenergic receptors were comparable between lean and obese animals. Properties of phosphofructokinase from obese and lean hearts were similar. High extracellular Ca2+ concentration, which activated phosphofructokinase in hearts from lean animals and phosphorylase in all hearts, failed to activate phosphofructokinase in hearts from obese rats. The data indicate that the failure of adrenaline to activate phosphofructokinase in hearts from obese (fa/fa) rats results from a post-receptor defect in the as-yet unidentified Ca2+-dependent phosphofructokinase-activating reactions.
More Related Videos
09:40Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle
Published on: January 19, 2017
06:40Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Related Concept Videos
G-Protein Gated Ion Channels
Sensory organs,...
GPCRs Regulate Adenylyl Cylase Activity
Two...
cAMP-dependent Protein Kinase Pathways
Transducer Mechanism: Enzyme-Linked Receptors
Major types that are helpful drug targets include: