A multifaceted and multidisciplinary research program is proposed for study of neural mechanisms underlying prolonged changes that follow spinal cord or spinal root injury. Morphological, physiological and biochemical approaches are to be used in experimental animal models of situations with pertinence for human clinical problems. The eight projects are directed toward elucidating processes responsible for enduring reflex and sensory alterations (spinal shock, hyperreflexia, pathological pain, altered sensation), trophic effects between neurons and effector organs, and neural modulation of renal function. The overall goal is to provide a better foundation from which new therapeutic approaches to conditions arising from injuries of the spinal roots and spinal cord might evolve. The investigators are faculty with full or joint appointments in the Department of Physiology; the Department has provided substantial space and facilities for the program. A scientific review panel, consisting of established scientists, with no relation to the project, from within and from other institutions is suggested as external monitors and advisors.