A gain-of-function HCN4 mutant in the HCN domain is responsible for inappropriate sinus tachycardia in a Spanish family.

In a family with inappropriate sinus tachycardia (IST), we identified a mutation (p.V240M) of the hyperpolarization-activated cyclic nucleotide-gated type 4 (HCN4) channel, which contributes to the pacemaker current (I) in human sinoatrial node cells. Here, we clinically study fifteen family members and functionally analyze the p.

Empagliflozin and Dapagliflozin Increase Na and Inward Rectifier K Current Densities in Human Cardiomyocytes Derived from Induced Pluripotent Stem Cells (hiPSC-CMs).

Dapagliflozin (dapa) and empagliflozin (empa) are sodium-glucose cotransporter-2 inhibitors (SGLT2is) that reduce morbidity and mortality in heart failure (HF) patients. Sodium and inward rectifier K currents (I and I), carried by Nav1.5 and Kir2.

A Cantú syndrome mutation produces dual effects on KATP channels by disrupting ankyrin B regulation.

ATP-sensitive potassium (KATP) channels composed of Kir6.x and sulfonylurea receptor (SURs) subunits couple cellular metabolism to electrical activity. Cantú syndrome (CS) is a rare disease caused by mutations in the genes encoding Kir6.

Zfhx3 Transcription Factor Represses the Expression of Gene and Decreases Sodium Current Density (I).

The and genes encode the zinc finger homeobox 3 (Zfhx3) transcription factor (TF) and the human cardiac Na channel (Nav1.5), respectively. The effects of Zfhx3 on the expression of the Nav1.

Tbx5 variants disrupt Nav1.5 function differently in patients diagnosed with Brugada or Long QT Syndrome.

Aims: The transcription factor Tbx5 controls cardiogenesis and drives Scn5a expression in mice. We have identified two variants in TBX5 encoding p. D111Y and p.

The p.P888L SAP97 polymorphism increases the transient outward current (I) and abbreviates the action potential duration and the QT interval.

Synapse-Associated Protein 97 (SAP97) is an anchoring protein that in cardiomyocytes targets to the membrane and regulates Na and K channels. Here we compared the electrophysiological effects of native (WT) and p.P888L SAP97, a common polymorphism.