A 13-MER PEPTIDE OF A BRAIN INJURY-DERIVED PROTEIN SUPPORTS NEURONAL SURVIVAL AND RESCUES NEURONS FROM INJURY CAUSED BY GLUTAMATE

Neuronal survival is mediated by several kinds of proteins. Among thes e, neurotrophic factors play important roles in the nervous system by supporting neuronal activity and survival. It has been suggested recen tly that certain factors promote neuronal survival in the case of brai n injury. To examine this possibility, we purified a novel neurotrophi c factor from Gelfoam that was implanted at the site of injury caused in neonatal rats. During amino acid sequence analysis, we found that a fragmental peptide of this neurotrophic protein consisting of 13 amin o acids showed neurotrophic activity. This 13-mer peptide promoted sur vival of septal cholinergic and mesencephalic dopaminergic neurons in culture and rescued hippocampal neurons from injury caused by glutamat e in culture. This peptide rescued neurons from cell death caused by g lutamate, even when added 4.5 h after glutamate exposure.