Cardiac transient outward potassium current

The cardiac action potential has five phases. Ito1 is active during phase 1, causing a fast repolarization of the action potential

The cardiac transient outward potassium current (referred to as Ito1 or Ito[1] ) is one of the ion currents across the cell membrane of heart muscle cells. It is the main contributing current during the repolarizing phase 1 of the cardiac action potential. It is a result of the movement of positively charged potassium (K+) ions from the intracellular to the extracellular space. Ito1 is complemented with Ito2 resulting from Cl− ions to form the transient outward current Ito.

  1. ^ Niwa N, Nerbonne JM (January 2010). "Molecular determinants of cardiac transient outward potassium current (I(to)) expression and regulation". Journal of Molecular and Cellular Cardiology. 48 (1): 12–25. doi:10.1016/j.yjmcc.2009.07.013. PMC 2813406. PMID 19619557.