Location, location, location: the organization and roles of potassium channels in mammalian motoneurons

The spatial and temporal balance of spinal α-motoneuron (αMN) intrinsic membrane conductances underlies the neural output final common pathway for motor commands. Although complete set precise localization αMN K+ channels their respective outward remain unsettled, important channel subtypes have now been documented, including Kv1, Kv2, Kv7, TASK, HCN SK isoforms. Unique kinetics gating parameters allow these to differentially shape and/or modify firing properties, recent immunohistochemical K+-channel complexes reveals a framework in which distribution focal clustering within different surface compartments is highly tuned physiological function. Moreover, evolved regulatory mechanisms enable specific operate over variable levels activity contribute either state-dependent enhancement or diminution firing. While data suggest an additional, non-conducting role clustered Kv2.1 formation endoplasmic reticulum–plasma junctions postsynaptic C-bouton synapses, electrophysiological evidence demonstrates that conducting effectively regulate firing, especially during periods high cholinergic C-boutons are engaged. Intense cell injury rapidly disrupts organization αMNs further impacts role. Thus, play critical processing potential therapeutic targets diseases affecting excitability output, amyotrophic lateral sclerosis.