[Responses of lumbar flexor motoneurons to stimulation of limb afferents]

Abstract

Interaction of PSPs elicited by stimulation of hindlimb and forelimb afferent nerves was studied in lumbar flexor motoneurons of anesthetized cats. Activation of forelimb afferents evoked EPSPs of considerable duration; no IPSPs were observed. Stimulation of hindlimb flexor afferents evoked EPSPs in the same motoneurons, their early component being of segmental origin and their late component--of spino-bulbo-spinal one. Interaction of afferent systems of fore--and hindlimbs caused a long-lasting depression of EPSPs. The depression of EPSPs was not followed by generation of IPSPs in motoneurons, Possible integrative levels of interlimb inhibitory coordination are discussed.