Role of Protein Synthesis and Monoamines in the Production of Long-Term Potentiation in the Rat Hippocampal Slice.

摘要

Long-term potentiation (LTP) in the hippocampus is a longlasting enhancement of synaptic efficacy produced by brief, highfrequency stimulation of afferents. The long duration of LTP, and implication of the hippocampus in learning, has generated interest in LTP as an appropriate model, and perhaps a candidate mechanism, for learning and memory. Thus, it is important to understand the mechanisms of LTP, and also to investigate mechanisms already implicated in learning and memory. Three major questions were addressed in my study, based upon what is known about the cellular mechanisms of learning and memory. First, since inhibitors of protein synthesis are amnestic in a variety of iearning paradigms, can protein synthesis inhibitors also impair production of LTP? Second, since the monoamine neurotransmitters norepinephrine (NE) and serotonin (5-HT) have both been implicated in performance of learning paradigms, what is the effect of depletion of either of these monoamines on LTP? Finally, since NE has been shown to produce a long-lasting potentiation in the dentate gyrus, what are the mechanisms behind this potentiation, compared to LTP?