Dataset Information

Extraocular muscle characteristics related to myasthenia gravis susceptibility.

ABSTRACT:

Background

The pathogenesis of extraocular muscle (EOM) weakness in myasthenia gravis might involve a mechanism specific to the EOM. The aim of this study was to investigate characteristics of the EOM related to its susceptibility to myasthenia gravis.

Methods

Female F344 rats and female Sprague-Dawley rats were assigned to experimental and control groups. The experimental group received injection with Ringer solution containing monoclonal antibody against the acetylcholine receptor (AChR), mAb35 (0.25 mg/kg), to induce experimental autoimmune myasthenia gravis, and the control group received injection with Ringer solution alone. Three muscles were analyzed: EOM, diaphragm, and tibialis anterior. Tissues were examined by light microscopy, fluorescence histochemistry, and transmission electron microscopy. Western blot analysis was used to assess marker expression and ELISA analysis was used to quantify creatine kinase levels. Microarray assay was conducted to detect differentially expressed genes.

Results

In the experimental group, the EOM showed a simpler neuromuscular junction (NMJ) structure compared to the other muscles; the NMJ had fewer synaptic folds, showed a lesser amount of AChR, and the endplate was wider compared to the other muscles. Results of microarray assay showed differential expression of 54 genes in the EOM between the experimental and control groups.

Conclusion

Various EOM characteristics appear to be related to the increased susceptibility of the EOM and the mechanism of EOM weakness in myasthenia gravis.

SUBMITTER: Liu R

PROVIDER: S-EPMC3568149 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Publications

Extraocular muscle characteristics related to myasthenia gravis susceptibility.

Liu Rui R Xu Hanpeng H Wang Guiping G Li Jie J Gou Lin L Zhang Lihua L Miao Jianting J Li Zhuyi Z

PloS one 20130208 2

<h4>Background</h4>The pathogenesis of extraocular muscle (EOM) weakness in myasthenia gravis might involve a mechanism specific to the EOM. The aim of this study was to investigate characteristics of the EOM related to its susceptibility to myasthenia gravis.<h4>Methods</h4>Female F344 rats and female Sprague-Dawley rats were assigned to experimental and control groups. The experimental group received injection with Ringer solution containing monoclonal antibody against the acetylcholine recept ...[more]

PMID: 23409007

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Dataset Information

Extraocular muscle characteristics related to myasthenia gravis susceptibility.

Background

Methods

Results

Conclusion

Publications

Extraocular muscle characteristics related to myasthenia gravis susceptibility.

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