Figure 1. Ion channels regulated by S-nitrosylation in the cardiac myocyte.
So far, characterized: the sodium channel, which generates a rapid depolarization; the L-type calcium channel, which generates the inward Ca2+ current; the ryanodine receptor (RyR2) calcium release channel of the sarcoplasmic reticulum; the transient outward potassium channel ITo, which activates rapidly upon depolarization; IKur, IKr and IKs which generates the delayed rectifier. The figure also includes the source of NO, the NO synthases NOS1 and NOS3 and the oxidases that are present in the cardiac cell. XOR, xanthine oxidoreductase, NOS, nitric oxide synthase.