The sinoatrial node is perhaps one of the most important tissues in the entire body: it is the
natural pacemaker of the heart, making it responsible for initiating each-and-every normal …

Phosphodiesterases (PDEs) are the principal superfamily of enzymes responsible for
degrading the secondary messengers 3′, 5′-cyclic nucleotides cAMP and cGMP. Their …

Rationale: Chronic elevation of 3′-5′-cyclic adenosine monophosphate (cAMP) levels
has been associated with cardiac remodeling and cardiac hypertrophy. However …

Aims Sino-atrial node (SAN) automaticity is an essential mechanism of heart rate generation
that is still not completely understood. Recent studies highlighted the importance of …

cAMP/PKA signalling is compartmentalised with tight spatial and temporal control of signal
propagation underpinning specificity of response. The cAMP-degrading enzymes …

Atrial fibrillation (AF) is prevalent in hypertension and elevated angiotensin II (Ang II);
however, the mechanisms by which Ang II leads to AF are poorly understood. Here, we …

Key points Sinoatrial node (SAN) function declines with age; however, not all individuals
age at the same rate and health status can vary from fit to frail. Frailty was quantified in …

Background: Atrial fibrillation (AF) commonly occurs in hypertension and in association with
elevated Ang II (angiotensin II) levels. The specific mechanisms underlying Ang II–mediated …

Rationale: Phosphodiesterase 2 is a dual substrate esterase, which has the unique property
to be stimulated by cGMP, but primarily hydrolyzes cAMP. Myocardial phosphodiesterase 2 …

Previous studies have shown that ventricular myocytes from female rats have smaller
contractions and Ca 2+ transients than males. As cardiac contraction is regulated by the …