Cortical ChAT(+) neurons co-transmit acetylcholine and GABA in a target- and brain-region-specific manner.

Citation:

Granger AJ, Wang W, Robertson K, El-Rifai M, Zanello AF, Bistrong K, Saunders A, Chow BW, Nuñez V, García MT, et al. Cortical ChAT(+) neurons co-transmit acetylcholine and GABA in a target- and brain-region-specific manner. eLife. 2020;9.
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Abstract:

The mouse cerebral cortex contains neurons that express choline acetyltransferase (ChAT) and are a potential local source of acetylcholine. However, the neurotransmitters released by cortical ChAT(+) neurons and their synaptic connectivity are unknown. We show that the nearly all cortical ChAT(+) neurons in mice are specialized VIP(+) interneurons that release GABA strongly onto other inhibitory interneurons and acetylcholine sparsely onto layer 1 interneurons and other VIP(+)/ChAT(+) interneurons. This differential transmission of ACh and GABA based on the postsynaptic target neuron is reflected in VIP(+)/ChAT(+) interneuron pre-synaptic terminals, as quantitative molecular analysis shows that only a subset of these are specialized to release acetylcholine. In addition, we identify a separate, sparse population of non-VIP ChAT(+) neurons in the medial prefrontal cortex with a distinct developmental origin that robustly release acetylcholine in layer 1. These results demonstrate both cortex-region heterogeneity in cortical ChAT(+) interneurons and target-specific co-release of acetylcholine and GABA.

Last updated on 07/29/2021