Header

UZH-Logo

Maintenance Infos

Sprouting of brainstem-spinal tracts in response to unilateral motor cortex stroke in mice


Bachmann, Lukas C; Lindau, Nicolas T; Felder, Petra; Schwab, Martin E (2014). Sprouting of brainstem-spinal tracts in response to unilateral motor cortex stroke in mice. Journal of Neuroscience, 34(9):3378-3389.

Abstract

After a stroke to the motor cortex, sprouting of spared contralateral corticospinal fibers into the affected hemicord is one mechanism thought to mediate functional recovery. Little is known, however, about the role of the phylogenetically old, functionally very important brainstem-spinal systems. Adult mice were subjected to a unilateral photothrombotic stroke of the right motor cortex ablating 90% of the cross-projecting corticospinal cells. Unilateral retrograde tracing from the left cervical spinal hemicord devoid of its corticospinal input revealed widespread plastic responses in different brainstem nuclei 4 weeks after stroke. Whereas some nuclei showed no change or a decrease of their spinal projections, several parts of the medullary reticular formation as well as the spinally projecting raphe nuclei increased their projections to the cortically denervated cervical hemicord by 1.2- to 1.6-fold. The terminal density of corticobulbar fibers from the intact, contralesional cortex, which itself formed a fivefold expanded connection to the ipsilateral spinal cord, increased up to 1.6-fold specifically in these plastic, caudal medullary nuclei. A second stroke, ablating the originally spared motor cortex, resulted in the reappearance of the deficits that had partially recovered after the initial right-sided stroke, suggesting dependence of recovered function on the spared cortical hemisphere and its direct corticospinal and indirect corticobulbospinal connections.

Abstract

After a stroke to the motor cortex, sprouting of spared contralateral corticospinal fibers into the affected hemicord is one mechanism thought to mediate functional recovery. Little is known, however, about the role of the phylogenetically old, functionally very important brainstem-spinal systems. Adult mice were subjected to a unilateral photothrombotic stroke of the right motor cortex ablating 90% of the cross-projecting corticospinal cells. Unilateral retrograde tracing from the left cervical spinal hemicord devoid of its corticospinal input revealed widespread plastic responses in different brainstem nuclei 4 weeks after stroke. Whereas some nuclei showed no change or a decrease of their spinal projections, several parts of the medullary reticular formation as well as the spinally projecting raphe nuclei increased their projections to the cortically denervated cervical hemicord by 1.2- to 1.6-fold. The terminal density of corticobulbar fibers from the intact, contralesional cortex, which itself formed a fivefold expanded connection to the ipsilateral spinal cord, increased up to 1.6-fold specifically in these plastic, caudal medullary nuclei. A second stroke, ablating the originally spared motor cortex, resulted in the reappearance of the deficits that had partially recovered after the initial right-sided stroke, suggesting dependence of recovered function on the spared cortical hemisphere and its direct corticospinal and indirect corticobulbospinal connections.

Statistics

Citations

Dimensions.ai Metrics
20 citations in Web of Science®
20 citations in Scopus®
21 citations in Microsoft Academic
Google Scholar™

Altmetrics

Downloads

48 downloads since deposited on 05 Feb 2015
24 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > Brain Research Institute
Dewey Decimal Classification:570 Life sciences; biology
610 Medicine & health
Date:26 February 2014
Deposited On:05 Feb 2015 11:43
Last Modified:15 Feb 2018 03:45
Publisher:Society for Neuroscience
ISSN:0270-6474
OA Status:Hybrid
Free access at:Publisher DOI. An embargo period may apply.
Publisher DOI:https://doi.org/10.1523/JNEUROSCI.4384-13.2014
PubMed ID:24573294

Download

Download PDF  'Sprouting of brainstem-spinal tracts in response to unilateral motor cortex stroke in mice'.
Preview
Content: Published Version
Filetype: PDF
Size: 4MB
View at publisher