title: Co-expression of GAP-43 and nNOS in avulsed motoneurons and their potential role for motoneuron regeneration.
abstract: Neuronal nitric oxide synthase (nNOS) is induced after axonal injury. The role of induced nNOS in injured neurons is not well established. In the present study, we investigated the co-expression of nNOS with GAP-43 in spinal motoneurons following axonal injury. The role of induced nNOS was discussed and evaluated. In normal rats, spinal motoneurons do not express nNOS or GAP-43. Following spinal root avulsion, expression of nNOS and GAP-43 were induced and colocalized in avulsed motoneurons. Reimplantation of avulsed roots resulted in a remarkable decrease of GAP-43- and nNOS-IR in the soma of the injured motoneurons. A number of GAP-43-IR regenerating motor axons were found in the reimplanted nerve. In contrast, the nNOS-IR was absent in reimplanted nerve. These results suggest that expression of GAP-43 in avulsed motoneurons is related to axonal regeneration whereas nNOS is not.
authors.affiliation: Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
authors.forename: Qiuju
authors.initials: Q
authors.lastname: Yuan
authors.forename: Bing
authors.initials: B
authors.lastname: Hu
authors.forename: Tak-Ho
authors.initials: TH
authors.lastname: Chu
authors.forename: Huanxing
authors.initials: H
authors.lastname: Su
authors.forename: Wenming
authors.initials: W
authors.lastname: Zhang
authors.forename: Kwok-Fai
authors.initials: KF
authors.lastname: So
authors.forename: Zhixiu
authors.initials: Z
authors.lastname: Lin
authors.forename: Wutian
authors.initials: W
authors.lastname: Wu
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D019922:GAP-43 Protein / Q000378:metabolism*; D009046:Motor Neurons / Q000201:enzymology / Q000378:metabolism*; D009416:Nerve Regeneration; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D019922:GAP-43 Protein; D052248:Nitric Oxide Synthase Type I