Induction of constitutively active acetylcholine-activated K+ current, CA IKACh, in human AF. Single channel IK1 and CA IKACh currents (A) and mean (±SE) open probabilities (B), recorded at -120 mV in atrial cells from patients in SR (□) and AF (■). *=P<0.05 vs SR. C, Potential signalling mechanism of increased CA IKACh in AF. In SR, IKACh may require channel phosphorylation by calmodulin-dependent protein kinase (PK) II (CaMKII), PKG and PKC.12 In AF, CA IKACh may result from upregulation of PKCε.12
A&B based on data in10 with permission from Lippincott Williams & Wilkins.