Comparison of effects of long-term treatment with NGF on expression of RP transcripts as determined by SAGE and real-time PCR. Changes in expression are expressed as fold up- or down-regulation by NGF. Up-regulated transcripts are given as the ratio of normalized tag numbers +NGF/-NGF and are expressed as positive values. Transcripts that are down-regulated by NGF are given as the ratio of normalized tag numbers -NGF/+NGF and are expressed as negative values. Values for real-time PCR are given as means ± SE (n = 4-6) and were normalized against the levels of beta actin message.