BDNF-mediated rescue of axotomized motor neurones decreases with increasing dose.
Direct application of brain-derived neurotrophic factor (BDNF) to the cut end of axotomized immature motor neurones had only transient survival-promoting effects. Therefore, we have examined whether additional delivery of BDNF with repeated subcutaneous injections (1 mg/ml) could potentiate this short-term rescue of the lesioned sciatic and facial motor neurones in neonatal rats. Direct application of BDNF combined with intermittent (3-day intervals) injections slightly improved motor neurone survival. However, when BDNF was injected daily in addition to the direct application, the number of surviving lesioned motor neurones was markedly reduced. These findings, corroborated by results in embryonic spinal cord cultures, show that a dose-dependent reversal of BDNF-mediated positive effects on motor neurones occurs in vivo.
Division of Clinical Neurophysiology, Centre Médical Universitaire, Geneva, Switzerland.
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Vejsada
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D000818:Animals; D001369:Axons / Q000502:physiology*; D019208:Brain-Derived Neurotrophic Factor; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D005154:Facial Nerve / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D009046:Motor Neurons / Q000187:drug effects* / Q000201:enzymology; D009414:Nerve Growth Factors / Q000494:pharmacology*; D009419:Nerve Tissue Proteins / Q000494:pharmacology*; D051381:Rats; D012584:Sciatic Nerve / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D013116:Spinal Cord / Q000166:cytology
D019208:Brain-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D002795:Choline O-Acetyltransferase