Limb immobilization alters functional electrophysiological parameters of sciatic nerve
Immobilization, used in clinical practice to treat traumatologic problems, causes changes in muscle, but it is not known whether changes also occur in nerves. We investigated the effects of immobilization on excitability and compound action potential (CAP) and the ultrastructure of the rat sciatic n...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Associação Brasileira de Divulgação Científica
2013-08-01
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| Series: | Brazilian Journal of Medical and Biological Research |
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| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2013000800715&lng=en&tlng=en |
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| author | J.S.M. Alves J.H. Leal-Cardoso F.F.U. Santos-Junior P.S. Carlos R.C. Silva C.M. Lucci S.N. Bao V.M. Ceccatto R. Barbosa |
| author_facet | J.S.M. Alves J.H. Leal-Cardoso F.F.U. Santos-Junior P.S. Carlos R.C. Silva C.M. Lucci S.N. Bao V.M. Ceccatto R. Barbosa |
| author_sort | J.S.M. Alves |
| collection | DOAJ |
| description | Immobilization, used in clinical practice to treat traumatologic problems, causes changes in muscle, but it is not known whether changes also occur in nerves. We investigated the effects of immobilization on excitability and compound action potential (CAP) and the ultrastructure of the rat sciatic nerve. Fourteen days after immobilization of the right leg of adult male Wistar rats (n=34), animals were killed and the right sciatic nerve was dissected and mounted in a moist chamber. Nerves were stimulated at a baseline frequency of 0.2 Hz and tested for 2 min at 20, 50, and 100 Hz. Immobilization altered nerve excitability. Rheobase and chronaxy changed from 3.13±0.05 V and 52.31±1.95 µs (control group, n=13) to 2.84±0.06 V and 59.71±2.79 µs (immobilized group, n=15), respectively. Immobilization altered the amplitude of CAP waves and decreased the conduction velocity of the first CAP wave (from 93.63±7.49 to 79.14±5.59 m/s) but not of the second wave. Transmission electron microscopy showed fragmentation of the myelin sheath of the sciatic nerve of immobilized limbs and degeneration of the axon. In conclusion, we demonstrated that long-lasting leg immobilization can induce alterations in nerve function. |
| first_indexed | 2024-12-14T00:03:49Z |
| format | Article |
| id | doaj.art-b0941da8f2bd4a05bf90abb34b22d3b1 |
| institution | Directory Open Access Journal |
| issn | 1414-431X |
| language | English |
| last_indexed | 2024-12-14T00:03:49Z |
| publishDate | 2013-08-01 |
| publisher | Associação Brasileira de Divulgação Científica |
| record_format | Article |
| series | Brazilian Journal of Medical and Biological Research |
| spelling | doaj.art-b0941da8f2bd4a05bf90abb34b22d3b12022-12-21T23:26:10ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research1414-431X2013-08-0146871572110.1590/1414-431X20132626S0100-879X2013000800715Limb immobilization alters functional electrophysiological parameters of sciatic nerveJ.S.M. AlvesJ.H. Leal-CardosoF.F.U. Santos-JuniorP.S. CarlosR.C. SilvaC.M. LucciS.N. BaoV.M. CeccattoR. BarbosaImmobilization, used in clinical practice to treat traumatologic problems, causes changes in muscle, but it is not known whether changes also occur in nerves. We investigated the effects of immobilization on excitability and compound action potential (CAP) and the ultrastructure of the rat sciatic nerve. Fourteen days after immobilization of the right leg of adult male Wistar rats (n=34), animals were killed and the right sciatic nerve was dissected and mounted in a moist chamber. Nerves were stimulated at a baseline frequency of 0.2 Hz and tested for 2 min at 20, 50, and 100 Hz. Immobilization altered nerve excitability. Rheobase and chronaxy changed from 3.13±0.05 V and 52.31±1.95 µs (control group, n=13) to 2.84±0.06 V and 59.71±2.79 µs (immobilized group, n=15), respectively. Immobilization altered the amplitude of CAP waves and decreased the conduction velocity of the first CAP wave (from 93.63±7.49 to 79.14±5.59 m/s) but not of the second wave. Transmission electron microscopy showed fragmentation of the myelin sheath of the sciatic nerve of immobilized limbs and degeneration of the axon. In conclusion, we demonstrated that long-lasting leg immobilization can induce alterations in nerve function.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2013000800715&lng=en&tlng=enImmobilizationSciatic nerveCompound action potentialConduction velocityRheobaseChronaxy |
| spellingShingle | J.S.M. Alves J.H. Leal-Cardoso F.F.U. Santos-Junior P.S. Carlos R.C. Silva C.M. Lucci S.N. Bao V.M. Ceccatto R. Barbosa Limb immobilization alters functional electrophysiological parameters of sciatic nerve Brazilian Journal of Medical and Biological Research Immobilization Sciatic nerve Compound action potential Conduction velocity Rheobase Chronaxy |
| title | Limb immobilization alters functional electrophysiological parameters of sciatic nerve |
| title_full | Limb immobilization alters functional electrophysiological parameters of sciatic nerve |
| title_fullStr | Limb immobilization alters functional electrophysiological parameters of sciatic nerve |
| title_full_unstemmed | Limb immobilization alters functional electrophysiological parameters of sciatic nerve |
| title_short | Limb immobilization alters functional electrophysiological parameters of sciatic nerve |
| title_sort | limb immobilization alters functional electrophysiological parameters of sciatic nerve |
| topic | Immobilization Sciatic nerve Compound action potential Conduction velocity Rheobase Chronaxy |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2013000800715&lng=en&tlng=en |
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