Axonal α7 nicotinic acetylcholine receptors modulate glutamatergic signaling and synaptic vesicle organization in ventral hippocampal projections

• Published in: Frontiers in neural circuits Vol. 16; p. 978837
• Main Authors: Zhong, Chongbo, Akmentin, Wendy, Role, Lorna W, Talmage, David A
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 23-09-2022; Frontiers Media S.A
• Subjects: Acetylcholine receptors (nicotinic); alpha7 Nicotinic Acetylcholine Receptor - metabolism; Animals; Axons; Axons - metabolism; Cholinergic Agents; cholinergic modulation; Glutamatergic transmission; Glutamic Acid; Hippocampus; Hippocampus - metabolism; Laboratory animals; Ligands; Mice; Neural Circuits; neurotransmitter release; optogenetics; Receptors, Nicotinic - metabolism; Synaptic Transmission - physiology; synaptic vesicle fusion; Synaptic Vesicles - metabolism; α7 nicotinic acetylcholine receptor; glutamatergic transmission; cholinergic modulation; iGluSnFr; optogenetics; electron microscopy; synaptic vesicle fusion; neurotransmitter release; α7 nicotinic acetylcholine receptor
• ISSN: 1662-5110; 1662-5110
• DOI: 10.3389/fncir.2022.978837

Modulation of the release of glutamate by activation of presynaptic nicotinic acetylcholine receptors (nAChRs) is one of the most prevalent mechanism of nicotinic facilitation of glutamatergic transmission in cortico-limbic circuits. By imaging gene chimeric co-cultures from mouse, we examined the role of α7* nAChRs mediated cholinergic modulation of glutamate release and synaptic vesicle organization in ventral hippocampal projections. We directly visualized exogenous and endogenous cholinergic facilitation of glutamate release in this specialized preparation of circuits
. Disrupting α7* nAChRs mediated cholinergic signaling genetically or pharmacologically diminished cholinergic facilitation of glutamate release at presynaptic terminals. Alteration of α7* nAChRs mediated cholinergic signaling along glutamatergic axons also decreased functional synaptic vesicle clustering to presynaptic terminals. These findings suggest that presynaptic α7* nAChRs contribute to cholinergic modulation of glutamate release and synaptic vesicle organization.