Regeneration And TransplantationIncrease in cytochrome oxidase activity in regenerating nerve fibers of hemitransected spinal cord in the ratLiu, Ying-Ying; Wong-Riley, M. T. T.1; Liu, Hui-Ling; Jia, Yi; Jiao, Xi-Ying; Wang, Chun-Ting; You, Si-Wei; Ju, GongCAAuthor Information Institute of Neurosciences, The Fourth Military Medical University, 17 Chang Le Xi Road, Xi'an 710032, China; 1Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA CACorresponding Author Received 17 July 2001; accepted 8 August 2001 NeuroReport: October 29th, 2001 - Volume 12 - Issue 15 - p 3239-3242 Buy Abstract We explored the possibility of cytochrome oxidase (CO) involvement in spinal cord regeneration in adult rats. The spinal cord was hemitransected at T9. After one month's survival, the animals were deeply anesthetized and perfused. The spinal cord segments including the lesion site were removed and sectioned horizontally for CO histochemistry. Under light microscope, a substantial number of CO-reactive nerve fibers and boutons were identified in the lateral funiculus adjacent to the lesion site. Under electron microscope, moderately to highly CO-reactive mitochondria could be seen within nerve fibers and boutons. Synaptic contacts were identified among them. The increase in CO activity in nerve fibers and boutons may indicate their high-energy demand for synaptic and spontaneous activity following spinal cord hemisection. © 2001 Lippincott Williams & Wilkins, Inc.