Meeting Abstract

S1.10  Tuesday, Jan. 4  The frequency dependent recruitment of interneurons in the rodent spinal cord ZHONG, Guisheng GZ*; HUSCH , Andreas AH; HARRIS-WARRICK, Ronald RMH; Cornell University Ithaca; Cornell University Ithaca; Cornell University Ithaca gz33@cornell.edu

Neuronal networks that control and coordinate locomotion such as swimming and walking in vertebrates are located in the lumbar spinal cord. The organization and function of the neural circuits, that are called central pattern generators (CPGs), are poorly understood. The development of powerful molecular genetic tools and the combination with electrophysiological analysis have recently contributed to a better understanding of roles of different identified CPG interneurons in mice. Recently, the properties and function of four cardinal types of genetically identified interneurons (V0, V1, V2, V3) have been investigated. Nevertheless, the roles of different neuron types during different locomotion speeds are not yet understood. Most studies are carried out at relatively stable locomotor frequencies. Studies from other species have shown that the function of spinal neurons may depend on the cycle frequency of locomotor output. Our previous result also indicates that the V2a interneuron, a class of local excitatory interneurons that selectively expresses the transcription factor Chx10, play a critical role in regulating locomotion left-right phase in mice in a frequency dependent way. Thus, it is reasonable to speculate the function of other spinal neurons may also be dependent on the cycle frequency in rodents. Here, we review our recent findings on the frequency dependent recruitment of V2a interneurons from the mouse spinal cord.