Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy
The time window for repair of the lower trunk is shorter than that of the upper trunk in patients with obstetric brachial plexus palsy. The denervated intrinsic muscles of the hand become irreversibly atrophic much faster than the denervated biceps. However, it is unclear whether the motor endplates...
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| Format: | Article |
| Language: | English |
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Wolters Kluwer Medknow Publications
2020-01-01
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| Series: | Neural Regeneration Research |
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| Online Access: | http://www.nrronline.org/article.asp?issn=1673-5374;year=2020;volume=15;issue=9;spage=1678;epage=1685;aulast=Li |
| _version_ | 1818846005352726528 |
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| author | Bo Li Liang Chen Yu-Dong Gu |
| author_facet | Bo Li Liang Chen Yu-Dong Gu |
| author_sort | Bo Li |
| collection | DOAJ |
| description | The time window for repair of the lower trunk is shorter than that of the upper trunk in patients with obstetric brachial plexus palsy. The denervated intrinsic muscles of the hand become irreversibly atrophic much faster than the denervated biceps. However, it is unclear whether the motor endplates of the denervated interosseous muscles degenerate more rapidly than those of the denervated biceps. In this study, we used a rat model of obstetric brachial plexus palsy of the right upper limb. C5–6 was lacerated distal to the intervertebral foramina, with concurrent avulsion of C7–8 and T1, with the left upper limb used as the control. Bilateral interossei and biceps were collected at 5 and 7 weeks. Immunofluorescence was used to assess the morphology of the motor endplates. Real-time quantitative polymerase chain reaction and western blot assay were used to assess mRNA and protein expression levels of acetylcholine receptor subunits (α, β and δ), rapsyn and β-catenin. Immunofluorescence microscopy showed that motor endplates in the denervated interossei were fragmented, while those in the denervated biceps were morphologically intact with little fragmentation. The number and area of motor endplates, relative to the control side, were significantly lower in the denervated interossei compared with the denervated biceps. mRNA and protein expression levels of acetylcholine receptor subunits (α, β and δ) were significantly lower, whereas β-catenin protein expression was higher, in the denervated interossei compared with the denervated biceps. The protein expression of rapsyn was higher in the denervated biceps than in the denervated interossei at 7 weeks. Our findings demonstrate that motor endplates of interossei are destabilized, whereas those of the biceps remain stable, in the rat model of obstetric brachial plexus palsy. All procedures were approved by the Experimental Animal Ethics Committee of Fudan University, China (approval No. DF-187) in January 2016. |
| first_indexed | 2024-12-19T05:38:40Z |
| format | Article |
| id | doaj.art-b540a1d9e99f470dbf3179136f058909 |
| institution | Directory Open Access Journal |
| issn | 1673-5374 |
| language | English |
| last_indexed | 2024-12-19T05:38:40Z |
| publishDate | 2020-01-01 |
| publisher | Wolters Kluwer Medknow Publications |
| record_format | Article |
| series | Neural Regeneration Research |
| spelling | doaj.art-b540a1d9e99f470dbf3179136f0589092022-12-21T20:34:04ZengWolters Kluwer Medknow PublicationsNeural Regeneration Research1673-53742020-01-011591678168510.4103/1673-5374.276341Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsyBo LiLiang ChenYu-Dong GuThe time window for repair of the lower trunk is shorter than that of the upper trunk in patients with obstetric brachial plexus palsy. The denervated intrinsic muscles of the hand become irreversibly atrophic much faster than the denervated biceps. However, it is unclear whether the motor endplates of the denervated interosseous muscles degenerate more rapidly than those of the denervated biceps. In this study, we used a rat model of obstetric brachial plexus palsy of the right upper limb. C5–6 was lacerated distal to the intervertebral foramina, with concurrent avulsion of C7–8 and T1, with the left upper limb used as the control. Bilateral interossei and biceps were collected at 5 and 7 weeks. Immunofluorescence was used to assess the morphology of the motor endplates. Real-time quantitative polymerase chain reaction and western blot assay were used to assess mRNA and protein expression levels of acetylcholine receptor subunits (α, β and δ), rapsyn and β-catenin. Immunofluorescence microscopy showed that motor endplates in the denervated interossei were fragmented, while those in the denervated biceps were morphologically intact with little fragmentation. The number and area of motor endplates, relative to the control side, were significantly lower in the denervated interossei compared with the denervated biceps. mRNA and protein expression levels of acetylcholine receptor subunits (α, β and δ) were significantly lower, whereas β-catenin protein expression was higher, in the denervated interossei compared with the denervated biceps. The protein expression of rapsyn was higher in the denervated biceps than in the denervated interossei at 7 weeks. Our findings demonstrate that motor endplates of interossei are destabilized, whereas those of the biceps remain stable, in the rat model of obstetric brachial plexus palsy. All procedures were approved by the Experimental Animal Ethics Committee of Fudan University, China (approval No. DF-187) in January 2016.http://www.nrronline.org/article.asp?issn=1673-5374;year=2020;volume=15;issue=9;spage=1678;epage=1685;aulast=Liacetylcholine receptor subunits; biceps; interossei; motor endplates; nerve regeneration; obstetric brachial plexus palsy; peripheral nerve injury |
| spellingShingle | Bo Li Liang Chen Yu-Dong Gu Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy Neural Regeneration Research acetylcholine receptor subunits; biceps; interossei; motor endplates; nerve regeneration; obstetric brachial plexus palsy; peripheral nerve injury |
| title | Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy |
| title_full | Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy |
| title_fullStr | Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy |
| title_full_unstemmed | Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy |
| title_short | Stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy |
| title_sort | stability of motor endplates is greater in the biceps than in the interossei in a rat model of obstetric brachial plexus palsy |
| topic | acetylcholine receptor subunits; biceps; interossei; motor endplates; nerve regeneration; obstetric brachial plexus palsy; peripheral nerve injury |
| url | http://www.nrronline.org/article.asp?issn=1673-5374;year=2020;volume=15;issue=9;spage=1678;epage=1685;aulast=Li |
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