Related Experiment Video
Updated: Oct 10, 2026

Isolation and Culture of Neonatal Mouse Cardiomyocytes
Published on: September 6, 2013
Angiotensin II stimulates cyclic ADP-ribose formation in neonatal rat cardiac myocytes
H Higashida1, J Zhang, M Hashii
1Department of Biochemical Genetics, Kanazawa University Graduate School of Medicine, 13-1 Takara-machi, Kanazawa 920-8640, Japan. haruhiro@med.kanazawa-u.ac.jp
Abstract:
To examine the role of cyclic ADP-ribose (cADP-ribose) as a second messenger downstream of angiotensin II (Ang II) receptor activation in the heart, ADP-ribosyl cyclase activity was measured in a crude membrane fraction of ventricular myocytes. Ang II at 10-100 nM increased ADP-ribosyl cyclase activity by 40-90% in the ventricular muscle of neonatal (2-4-day-old) rats, but not in fetal or adult hearts. This increase was inhibited by the Ang II antipeptide. Stimulation of ADP-ribosyl cyclase was reproduced by GTP and guanosine 5'-[gamma-thio]triphosphate, and prevented by guanosine 5'-[beta-thio]diphosphate. Prior treatment of the rats with cholera toxin A and B subunits also blocked the Ang II-induced activation. The density of Ang II receptors detected as [(3)H]Ang II binding was higher in neonatal than adult rats. These results demonstrate the existence of a signalling pathway from Ang II receptors to membrane-bound ADP-ribosyl cyclase in the ventricular muscle cell and suggest that the Ang II-induced increase in cADP-ribose synthesis is involved in the regulation of cardiac function and development.
Related Concept Videos
Antihypertensive Drugs: Angiotensin II Receptor Blockers
Heart Failure Drugs: Inhibitors of Renin-Angiotensin System
Transducer Mechanism: Enzyme-Linked Receptors
Major types that are helpful drug targets include:
Antihypertensive Drugs: Direct Renin Inhibitors
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...
Antihypertensive Drugs: Angiotensin-Converting Enzyme Inhibitors

