Dorsal root ganglion neurons up-regulate the expression of laminin-associated integrins after peripheral but not central axotomy
| Autor: | Staffan Cullheim, Stephen J. Kaufman, Henrik Hammarberg, Stefan Plantman, Wilhelm Wallquist, Johan Zelano |
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| Rok vydání: | 2004 |
| Předmět: |
Integrins
medicine.medical_treatment Integrin Schwann cell Rats Sprague-Dawley Dorsal root ganglion Laminin Ganglia Spinal medicine Animals Laminin binding Neurons biology General Neuroscience Axotomy Nerve injury Rats Up-Regulation Cell biology medicine.anatomical_structure Gene Expression Regulation nervous system Peripheral nervous system biology.protein Sciatic Neuropathy medicine.symptom Neuroscience |
| Zdroj: | The Journal of Comparative Neurology. 480:162-169 |
| ISSN: | 1096-9861 0021-9967 |
| DOI: | 10.1002/cne.20345 |
| Popis: | The favorable prognosis of regeneration in the peripheral nervous system after axonal lesions is generally regarded as dependent on the Schwann cell basal lamina. Laminins, a heterotrimeric group of basal lamina molecules, have been suggested to be among the factors playing this supportive role. For neurons to utilize laminin as a substrate for growth, an expression of laminin binding receptors, integrins, is necessary. In this study, we have examined the expression of laminin binding integrin subunits in dorsal root ganglion (DRG) neurons after transection to either their peripherally projecting axons, as in the sciatic nerve, followed by regeneration, or the centrally projecting axons in dorsal roots, followed by no or weak regenerative activity. In uninjured DRG, immunohistochemical staining revealed a few neurons expressing integrin subunit alpha6, whereas integrin subunits alpha7 and foremost beta1 were expressed in a majority of neurons. After an injury to the sciatic nerve, mRNAs encoding all three integrins were up-regulated in DRG neurons. By anterograde tracing, immunoreactivity for all studied integrins was also found in association with growing axons after a sciatic nerve crush lesion in vivo. In contrast, mRNA levels remained constant in DRG neurons after a dorsal root injury. Together with previous findings, this suggests that integrin subunits alpha6, alpha7, and beta1 have an important role in the regenerative response following nerve injury and that the lack of regenerative capacity following dorsal root injury could in part be explained by the absence of response in integrin regulation. |
| Databáze: | OpenAIRE |
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