Pathway
Cardiac conduction
The normal sequence of contraction of atria and ventricles of the heart require activation of groups of cardiac cells. The mechanism must elicit rapid changes in heart rate and respond to changes in autonomic tone. The cardiac action potential controls these functions. Action potentials are generated by the movement of ions through transmembrane ion channels in cardiac cells. Like skeletal myocytes (and axons), in the resting state, a given cardiac myocyte has a negative membrane potential. In both muscle types, after a delay (the absolute refractory period), K+ channels reopen and the resulting flow of K+ out of the cell causes repolarisation. The voltage-gated Ca2+ channels on the cardiac sarcolemma membrane are generally triggered by an influx of Na+ during phase 0 of the action potential. Cardiac muscle cells are so tightly bound that when one of these cells is excited the action potential spreads to all of them. The standard model used to understand the cardiac action potential is the action potential of the ventricular myocyte.
Continue reading
The action potential has 5 phases (numbered 0-4). Phase 4 describes the membrane potential when a cell is not being stimulated. The normal resting potential in the ventricular myocardium is between -85 to -95 mV. The K+ gradient across the cell membrane is the key determinant in the normal resting potential. Phase 0 is the rapid depolarisation phase in which electrical stimulation of a cell opens the closed, fast Na+ channels, causing a large influx of Na+ creating a Na+ current (INa+). This causes depolarisation of the cell. The slope of phase 0 represents the maximum rate of potential change and differs in contractile and pacemaker cells. Phase 1 is the inactivation of the fast Na+ channels. The transient net outward current causing the small downward deflection (the "notch" of the action potetial) is due to the movement of K+ and Cl- ions. In pacemaker cells, this phase is due to rapid K+ efflux and closure of L-type Ca2+ channels. Phase 2 is the plateau phase which is sustained by a balance of Ca2+ influx and K+ efflux. This phase sustains muscle contraction. Phase 3 of the action potential is where a concerted action of two outward delayed currents brings about repolarisation back down to the resting potential.
REACT:R-HSA-5576891Reactome
What the reference databases state
Statements
126 statements
126 statements · 1 reference database · Subject: Cardiac conduction · Sources: Reactome
- ABCC9 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- AHCYL1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- AKAP9 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ASPH participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1A1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1A2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1A3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1A4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1B1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1B2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP1B3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP2A1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
Show the remaining 114
- ATP2A2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP2A3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP2B1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP2B2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP2B3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ATP2B4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CACNA1C participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CACNA2D2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CACNB1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CACNB2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CACNG4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CALM1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CAMK2A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CAMK2B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CAMK2D participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CAMK2G participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CASQ1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CASQ2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CES1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- CLIC2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- DMPK participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FGF11 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FGF12 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FGF13 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FGF14 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FKBP1B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FXYD1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FXYD2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FXYD3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FXYD4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FXYD6 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- FXYD7 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- GATA4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- HIPK1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- HIPK2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ITPR1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ITPR2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ITPR3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KAT2B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNA5 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCND1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCND2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCND3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNE1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNE2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNE3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNE4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNE5 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNH2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNIP1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNIP2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNIP3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNIP4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNJ11 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNJ12 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNJ14 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNJ2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNJ4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK10 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK12 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK13 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK15 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK16 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK17 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK18 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK4 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK5 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK6 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK7 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNK9 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- KCNQ1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- MME participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- NKX2-5 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- NOS1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- NPPA participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- NPPC participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- NPR1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- NPR2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ORAI1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- ORAI2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- PLN participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- PRKACA participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- RANGRF participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- RYR1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- RYR2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- RYR3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN10A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN11A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN1A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN1B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN2A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN2B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN3A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN3B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN4A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN4B participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN5A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN7A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN8A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SCN9A participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SLC8A1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SLC8A2 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SLC8A3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SLN participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- SRI participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- STIM1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- TBX5 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- TNNI3 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- TRDN participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- TRPC1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only
- WWTR1 participates in Cardiac conductionProteinReactome R-HSA-5576891Inferred only