Cholinergic Afferent Stimulation Induces Axonal Function Plasticity in Adult Hippocampal Granule Cells

• DOI: 10.1016/j.neuron.2014.12.030
• Publication Date: 2015-01-08T21:21:22Z
• Authors: Katiuscia Martinello; Zhuo Huang; Rafael Lujan; Baouyen Tran; Masahiko Watanabe; Edward C. Cooper; David A. Brown; Mala M. Shah
• Keywords: Granule (geology)

Acetylcholine critically influences hippocampal-dependent learning. Cholinergic fibers innervate hippocampal neuron axons, dendrites, and somata. The effects of acetylcholine on axonal information processing, though, remain unknown. By stimulating cholinergic making electrophysiological recordings from dentate gyrus granule cells, we show that synaptically released preferentially lowered the action potential threshold, enhancing intrinsic excitability synaptic potential-spike coupling. These persisted for at least 30 min after stimulation paradigm were due to muscarinic receptor activation. This caused sustained elevation intracellular Ca2+ via T-type channels, as indicated by two-photon imaging. enhanced levels inhibited an KV7/M current, decreasing spike threshold. In support, immunohistochemistry revealed M1 receptor, CaV3.2, KV7.2/7.3 subunit localization in cell axons. Since alterations signaling affect neuronal firing patterns neurotransmitter release, this is unreported cellular mechanism which might, partly, enhance cognitive processing.