Cause for excitement

摘要

Axo-axonic cells (AACs) are interneu-rons that constitute the sole inputs to the axon initial segment of pyramidal cells and do not innervate other cell types. They are traditionally thought to provide only inhibitory input that is mediated by GABA (gamma-aminobutyric acid). However, writing in Science, Szabadics and co-workers report a surprising role for these cells: they can trigger GABA-mediated excitatory as well as inhibitory postsynaptic responses in adult pyramidal cells.