Thresholds for synaptic activation of transcription factors in hippocampus: correlation with long-term enhancement

作者：P F Worley, RV Bhat, Jay M. Baraban, Erickson CA, B. L. McNaughton, C. A. Barnes · 发表于：Journal of Neuroscience · 年份：1993 · DOI：10.1523/jneurosci.13-11-04776.1993 · 被引用次数：352 · 研究领域：Neuroscience and Neuropharmacology Research、Neurogenesis and neuroplasticity mechanisms、Memory and Neural Mechanisms

Recent studies suggest a role for rapid induction of transcription factors in stimulus-induced neuronal plasticity in the mammalian brain. Synaptic activation of transcription factors has been analyzed in the hippocampus using the long-term potentiation or enhancement (LTP/LTE) paradigm. Using this approach, several studies have identified transcription factors that are induced in hippocampal granule cells by NMDA receptor-dependent mechanisms; however, the link between long-term plasticity and activation of these genes has been called into question by reports suggesting that the thresholds for LTE and gene activation differ. To address this issue, we have used a chronic in vivo recording technique to monitor mRNA responses of several transcription factor genes to two different patterns of LTE-inducing electrical stimulation of entorhinal cortical afferents to hippocampus. One pattern consisted of 10 repetitions of a 20 or 25 msec train of pulses at 400 Hz (80 or 100 pulses total). This "10-train" pattern has been used in previous studies of LTE and produces robust synaptic enhancement lasting at least 3 d (Barnes, 1979). The other stimulation pattern consisted of 50 repetitions of a 20 msec train delivered at 400 Hz (400 pulses total), which is similar to parameters used in other studies reporting induction of c-fos in association with LTE (Dragunow et al., 1989; Jeffery et al., 1990; Abraham et al., 1992). Our results indicate that expression of zif268, monitored by in situ...