Dataset Information

Distinctive functional deficiencies in axonal conduction associated with two forms of cerebral white matter injury.

ABSTRACT:

Aims

This study determines whether assessment with compound action potentials (CAPs) can distinguish two different forms of cerebral white matter injury at the functional levels.

Methods

A pure demyelination model was induced in C57/BL6 adult mice by dietary supplementation of cuprizone (0.2%) for 6 weeks. Callosal L-N5-(1-Iminoethyl) ornithine (L-NIO) hydrochloride (27 mg/mL) was injected into the corpus callosum (CC) to induce a focal white matter stroke (WMS), resulting in both demyelination and axonal injury. White matter integrity was assessed by performing CAP recording, electron microscopy, and immunohistological and luxol fast blue (LFB) staining.

Results

Immunohistological and electron microscopic analyses confirmed the induction of robust demyelination in CC with cuprizone, and mixed demyelination and axonal damage with L-NIO. Electrophysiologically, cuprizone-induced demyelination significantly reduced the amplitude of negative peak 1 (N1), but increased the amplitude of negative peak 2 (N2), of the CAPs compared to the sham controls. However, cuprizone did not affect the axonal conduction velocity. In contrast, the amplitude and area of both N1 and N2 along with N1 axonal conduction velocity were dramatically decreased in L-NIO-induced WMS.

Conclusions

Concertedly, parameters of the CAPs offer a novel functional assessment strategy for cerebral white matter injury in rodent models.

SUBMITTER: Mu HF

PROVIDER: S-EPMC6698976 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Publications

Distinctive functional deficiencies in axonal conduction associated with two forms of cerebral white matter injury.

Mu Hong-Feng HF Gao Xu-Guang XG Li Si-Cheng SC Wei Peng-Ju PJ Zhao Yong-Fang YF Zhang Wen-Ting WT Wang Yun Y Gao Yan-Qin YQ

CNS neuroscience & therapeutics 20190529 9

<h4>Aims</h4>This study determines whether assessment with compound action potentials (CAPs) can distinguish two different forms of cerebral white matter injury at the functional levels.<h4>Methods</h4>A pure demyelination model was induced in C57/BL6 adult mice by dietary supplementation of cuprizone (0.2%) for 6 weeks. Callosal L-N5-(1-Iminoethyl) ornithine (L-NIO) hydrochloride (27 mg/mL) was injected into the corpus callosum (CC) to induce a focal white matter stroke (WMS), resulting in both ...[more]

PMID: 31140740

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Dataset Information

Distinctive functional deficiencies in axonal conduction associated with two forms of cerebral white matter injury.

Aims

Methods

Results

Conclusions

Publications

Distinctive functional deficiencies in axonal conduction associated with two forms of cerebral white matter injury.

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