Alterations in BDNF and NT-3 mRNAs in rat hippocampus after experimental brain trauma.
Previous studies have suggested that the neurotrophins brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) are neuroprotective or neurotrophic for certain subpopulations of hippocampal neurons following various brain insults. In the present study, the expression of BDNF and NT-3 mRNAs in rat hippocampus was examined after traumatic brain injury. Following lateral fluid percussion (FP) brain injury of moderate severity (2.0-2.1 atm) or sham injury, the hippocampi from adult rats were processed for the in situ hybridization localization of BDNF and NT-3 mRNAs using 35S-labeled cRNA probes at post-injury survival times of 1, 3, 6, 24 and 72 h. Unilateral FP injury markedly increased hybridization for BDNF mRNA in the dentate gyrus bilaterally which peaked at 3 h and remained above control levels for up to 72 h post-injury. A moderate increase in BDNF mRNA expression was also observed bilaterally in the CA3 region of the hippocampus at 1, 3, and 6 h after FP injury, but expression declined to control levels by 24 h. Conversely, NT-3 mRNA was significantly decreased in the dentate gyrus following FP injury at the 6 and 24 h survival times. These results demonstrate that FP brain injury differentially modulates expression of BDNF and NT-3 mRNAs in the hippocampus, and suggest that neurotrophin plasticity is a functional response of hippocampal neurons to brain trauma.
Hicks
R R
RR
Department of Clinical Sciences, University of Kentucky, Lexington 40536, USA.
Numan
S
S
Dhillon
H S
HS
Prasad
M R
MR
Seroogy
K B
KB
D000818:Animals; D001930:Brain Injuries / Q000209:etiology / Q000378:metabolism*; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D018891:Dentate Gyrus / Q000378:metabolism; D006624:Hippocampus / Q000293:injuries / Q000378:metabolism*; D008297:Male; D009414:Nerve Growth Factors / Q000235:genetics*; D009473:Neuronal Plasticity / Q000502:physiology; D020933:Neurotrophin 3; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D019208:Brain-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D020933:Neurotrophin 3; D012333:RNA, Messenger