A cardiac conduction process that modulates the extent of heart contraction, changing the force with which blood is propelled.

A G protein-coupled acetylcholine receptor signaling pathway that contributes to a decrease in frequency or rate of heart contraction through activation of the IKACh potassium channel. Binding of acetylcholine to a G protein-coupled acetylcholine receptor (muscarinic receptor) on the surface of the signal-receiving cell results in liberation of the G-beta/gamma complex from the alpha subunit. The G-beta/gamma complex binds directly to the inward-rectifying potassium channel IKACh. Once the ion channel is activated, potassium ions (K+) flow out of the cell and cause it to hyperpolarize. In its hyperpolarized state, action potentials cannot be fired as quickly as possible, which slows the heart rate.

An adrenergic receptor signaling pathway that contributes to an increase in frequency or rate of cardiac muscle contraction through phosphorylation and enhancement of the ryanodine receptor, a calcium-activated calcium-release channel found in the membrane of the sarcoplasmic reticulum. An adrenergic receptor-activated adenylate cyclase generates cAMP. cAMP then activates the cAMP-dependent protein kinase A (PKA), which phosphorylates the ryanodine receptor (RyR). PKA-phosphorylation of RyR enhances channel activity by sensitizing the channel to cytosolic calcium. Cytosolic calcium stimulates contractile proteins to promote muscle contraction.

A phospholipase C-activating G protein-coupled receptor signaling pathway initiated by angiotensin binding to its receptor on the surface of a target cell, and ending with the regulation of a downstream cellular process, e.g. transcription.

An adenylate cyclase-inhibiting adrenergic receptor signaling pathway which contributes to a circulatory system process carried out by the heart.

An angiotensin-mediated signaling pathway that contributes to a circulatory system process carried out by the heart, where the activated receptor transmits the signal via Gq-mediated activation of phospholipase C (PLC). PLC hydrolyses phosphatidylinositol 4,5-bisphosphate (PIP2) into the second messengers inositol-1,4,5,-triphosphate (IP3) and diacylglycerol (DAG). DAG activates protein kinase C (PKC), whilst IP3 binds intracellular receptors to induce the release of Ca2+ from intracellular stores.

An angiotensin receptor signaling pathway which contributes to a circulatory system process carried out by the heart.

Binding to a protein or protein complex contributing to the adhesion of two different types of cells.

Binding to a protein or protein complex that results in the connection of an AV node cell with a bundle of His cell and contributes to the communication between the two cells.

Binding to a protein or protein complex that results in the connection of an atrial cardiomyocyte with an AV node cell and contributes to the communication between the two cells.

Binding to a protein or protein complex that results in the connection of a Purkinje myocyte with an ventricular cardiac muscle cell and contributes to the communication between the two cells.

Binding to a protein or protein complex that results in the connection of a bundle of His cell with a Purkinje myocyte and contributes to the communication between the two cells.

Catalysis of the transmembrane transfer of a potassium ion by a voltage-gated channel through the plasma membrane of an AV node cardiac muscle cell contributing to the repolarization phase of an action potential. A voltage-gated channel is a channel whose open state is dependent on the voltage across the membrane in which it is embedded.

Binding to a protein or protein complex that results in the connection of an SA cardiomyocyte with an atrial cardiomyocyte and contributes to the communication between the two cells.

Enables the transmembrane transfer of a potassium ion by a voltage-gated channel through the plasma membrane of a Purkinje myocyte contributing to the repolarization phase of an action potential. A voltage-gated channel is a channel whose open state is dependent on the voltage across the membrane in which it is embedded.

Enables the transmembrane transfer of a potassium ion by a voltage-gated channel through the plasma membrane of a bundle of His cell contributing to the repolarization phase of an action potential. A voltage-gated channel is a channel whose open state is dependent on the voltage across the membrane in which it is embedded.

Enables the transmembrane transfer of a potassium ion by a voltage-gated channel through the plasma membrane of an atrial cardiomyocyte contributing to the repolarization phase of an action potential. A voltage-gated channel is a channel whose open state is dependent on the voltage across the membrane in which it is embedded.

Catalysis of the reaction: adenosine + H2O = inosine + NH3, in a double-stranded RNA molecule.

Catalysis of the extension of the 3' end of a DNA strand by one deoxynucleotide at a time. Cannot initiate a chain de novo; uses the RNA subunit of the telomerase enzyme complex as its template.