Voltage-sensitive ion channels in rhythmic motor systems.

Voltage-sensitive ionic currents shape both the firing properties of neurons and their synaptic integration within neural networks that drive rhythmic motor patterns. Persistent sodium currents underlie rhythmic bursting in respiratory neurons. H-type pacemaker currents can act as leak conductances in spinal motoneurons, and also control long-term modulation of synaptic release at the crayfish neuromuscular junction. Calcium currents travel in rostro-caudal waves with motoneuron activity in the spinal cord. Potassium currents control spike width and burst duration in many rhythmic motor systems. We are beginning to identify the genes that underlie these currents.