Modulatory Actions of Norepinephrine on Neural Circuits

Studies on the actions of the NE fiber system in the CNS have traditionally been conducted along two primary dimensions. At the systems level a major issue has been to resolve the consequences of NE release on circuit functions in noradren-ergically innervated areas. At the cellular level, the major question is how noradrenergic receptor activation leads to subsequent membrane actions and how such effects relate to events seen at the synaptic level. Our experience from past investigations is that there is a critical synergy between these two levels of analysis, and that progress at one level may generate insights critical for pursuing issues at the other.