Objective Physical or mental imbalance caused by harmful stimuli can induce stress to
maintain homeostasis. During chronic stress, the sympathetic nervous system is …

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels comprise a small
subfamily of proteins within the superfamily of pore-loop cation channels. In mammals, the …

▪ Abstract Hyperpolarization-activated cation currents, termed If, Ih, or Iq, were initially
discovered in heart and nerve cells over 20 years ago. These currents contribute to a wide …

Pacemaker activity of spontaneously active neurons,, and heart cells,, is controlled by a
depolarizing, mixed Na+/K+ current, named I h (or I f in the sinoatrial node of the heart),. This …

CYCLIC AMP acts as a second messenger in the modulation of several ion channels1–9
that are typically controlled by a phosphorylation process10. In cardiac pacemaker cells …

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels underlie the control of
rhythmic activity in cardiac and neuronal pacemaker cells. In HCN, the polarity of voltage …

The last two decades have witnessed the recognition of a significant relationship between
the autonomic nervous system and cardiovascular mortality, including sudden cardiac …

Background The clinical relevance of HRV was first appreciated in 1965 when Hon and Lee
6 noted that fetal distress was preceded by alterations in interbeat intervals before any …

Ion channels are membrane proteins that act as gated pathways for the movement of ions
across cell membranes. They play essential roles in the physiology of all cells. In recent …

Pacemaking is a basic physiological process, and the cellular mechanisms involved in this
function have always attracted the keen attention of investigators. The “funny”(I f) current …