Lesion-induced increase of BDNF is greater in the striatum of young versusold rat brain

Young (4-5 month old) and old (32-34 month old) Brown Norway/F344 hybrid ra ts were given unilateral 6-OHDA lesions of the nigrostriatal pathway, Four weeks later tissue from the lesioned or intact striatum or ventral midbrain was dissected and analyzed for brain-derived neurotrophic factor (BDNF) pr otein levels using an enzyme-linked immunosorbent assay. BDNF protein conte nt was greater in the lesioned striatum than in the intact striatum for all young rats, and the increased BDNF content in the lesioned striatum of you ng rats was directly correlated with severity of lesion as determined by ro tational scores. BDNF content in the lesioned striatum increased in less th an half of the old rats and was not significantly different than BDNF conte nt in the intact striatum. BDNF content in the lesioned substantia nigra/ve ntral tegmental area (SN/VTA) was greater than BDNF content in the intact S N/VTA for both young and old rats. These data suggest that an age-related d ifference in activity of at least one neurotrophic factor, BDNF, occur with in the denervated striatum following a neurotoxic lesion of the nigrostriat al pathway. (C) 2000 Academic Press.