Fig. 2. Quantitative analysis of linearly amplified messenger RNA (mRNA) in injured and uninjured hippocampal neurons. (  A ) Ribonuclease protection assay analysis of 100 ng linearly amplified hippocampal neuron mRNA with brain-derived neurotrophic factor (BDNF) riboprobe. mRNA expression in 5, 10, and 25 neurons is equivalent when normalized to the glyceraldehye-3-phosphate dehydrogenase (G3PDH) signal. CM = century marker (Ambion). (  B ) Ribonuclease protection assay analysis of glutathione peroxidase 1 (GPX-1) expression in uninjured (Fluoro-Jade–negative) and injured (Fluoro-Jade–positive) neurons in hippocampal subfields CA1, CA3, and dentate gyrus (DG) of one traumatic brain injury rat. (  C ) Expression of GPX-1 signal in Northern Blot analysis (  inset ) of pooled uninjured (from six rats) and pooled injured CA3 neurons with GPX-1 probe (from six rats) in digital light units (DLU) normalized to G3PDH expression. (  D ) Real-time polymerase chain reaction (PCR) analysis of BDNF expression in pooled uninjured and pooled injured CA3 neurons (all six traumatic brain injury rats).