REGENERATION AND TRANSPLANTATIONChondroitinase ABC promotes axonal regeneration of Clarke's neurons after spinal cord injuryYick, Leung-Wah1; Wu, Wutian1,3; So, Kwok-Fai1; Yip, Henry K.1; Shum, Daisy Kwok-Yan2Author Information 1Departments of Anatomy, Faculty of Medicine, The University of Hong Kong, Hong Kong 2Departments of Biochemistry, Faculty of Medicine, The University of Hong Kong, Hong Kong 3Corresponding Author: Wutian Wu Acknowledgements: This study was supported by research grants from the University of Hong Kong and the Hong Kong Research Grant Council. We thank Regeneron Pharmaceutical and Regeneron/Amgen Partners for their supply of BDNF. Received 22 December 1999; accepted 27 January 2000 NeuroReport: April 7, 2000 - Volume 11 - Issue 5 - p 1063-1067 Buy Abstract We examined whether enzymatic digestion of chondroitin sulfate (CS) promoted the axonal regeneration of neurons in Clarke's nucleus (CN) into a peripheral nerve (PN) graft following injury of the spinal cord. After hemisection at T11, a segment of PN graft was implanted at the lesion site. Either vehicle, brain-derived neurotrophic factor (BDNF) or chondroitinase ABC was applied at the implantation site. The postoperative survival period was 4 weeks. Treatment with vehicle or BDNF did not promote the axonal regeneration of CN neurons into the PN graft. Application of 2.5 unit/ml chondroitinase ABC resulted in a significant increase (12.8%) in the number of regenerated CN neurons. Double labeling with Fluoro-Gold and NADPH-diaphorase histochemistry showed that the regenerated CN neurons did not express nitric oxide synthase (NOS). Our results suggest that CS is inhibitory to the regeneration of CN neurons following injury of the spinal cord. © 2000 Lippincott Williams & Wilkins, Inc.