Neuroscience 2002 Abstract
| Presentation Number: | 535.5 |
|---|---|
| Abstract Title: | Electron microscopy studies of axons regenerating across a nerve conduit during local nitric oxide synthase inhibition in vivo. |
| Authors: |
McDonald, D. S.*1
; Zochodne, D. W.1
1Dept Clinical Neurosci, Univ Calgary, Calgary, Canada |
| Primary Theme and Topics |
Development - Transplantation and Regeneration -- Regeneration: PNS |
| Session: |
535. Transplantation and regeneration: regeneration--PNS II Poster |
| Presentation Time: | Tuesday, November 5, 2002 1:00 PM-2:00 PM |
| Location: | Hall A2-B3 C-33 |
| Keywords: | RAT, ULTRASTRUCTURE, PERIPHERAL NERVE, NERVE INJURY |
Recovery from peripheral nerve injuries is rarely complete. In a previous SFN abstract, we demonstrated the use of an injectable nerve regeneration conduit that allows direct manipulation of the regenerative microenvironment. Administration of a broad spectrum nitric oxide synthesis inhibitor (L-NAME) increased the number of regenerating myelinated fibers through the conduit following sciatic nerve transection in rats. In the present work, we address ultrastructural features of the regenerating nerve bridges that traversed an imposed 3mm gap inside the nerve conduits. Such bridges involve regrowth of axons not exposed to the products of Wallerian-like degeneration. Numbers and caliber of unmyelinated fibers in 20 sites from 5 systematically selected grids from each bridge/rat (n=8/group) were measured and size-number histograms constructed. Most unmyelinated regenerative profiles resembled those regrowing through degenerating nerve stumps: multiple closely apposed profiles sharing a common basement membrane and Schwann cell profile. As in the counts of myelinated fibers, there was a trend toward fewer unmyelinated profiles in bridges exposed to direct superfusion with L-NAME. Overall size profiles were similar in both groups suggesting that the NOS inhibitor promoted greater numbers of bridging axons, rather than accelerated maturation of axons into myelinated profiles.
Regenerating axons not directly exposed to products of Wallerian-like degeneration regrow as bundled axons closely apposed to Schwann cell processes. A broad spectrum NOS inhibitor appears to facilitate greater outgrowth of these fibers from the proximal nerve stump.
Supported by CIHR & AHFMR.
Regenerating axons not directly exposed to products of Wallerian-like degeneration regrow as bundled axons closely apposed to Schwann cell processes. A broad spectrum NOS inhibitor appears to facilitate greater outgrowth of these fibers from the proximal nerve stump.
Supported by CIHR & AHFMR.
Sample Citation:
[Authors]. [Abstract Title]. Program No. XXX.XX. 2002 Neuroscience Meeting Planner. Orlando, FL: Society for Neuroscience, 2002. Online.
Copyright © 2002-2026 Society for Neuroscience; all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication.
