The role of cholinergic system in neuronal plasticity: Focus on visual cortex and muscarinic receptors

Institute of Neuroscience (C.N.R.), 56100 Pisa, Italy.
Archives italiennes de biologie (Impact Factor: 1.49). 10/2008; 146(3-4):165-88. DOI: 10.4449/aib.v146i3.767
Source: PubMed


This review is focused on the basal forebrain (BFB) cholinergic system, cholinergic receptors and cholinoceptive target areas such as the neocortex, all of which are intimately involved in high cognitive functions and synaptic plasticity. The neurons of the BFB synthesize acetylcholine (ACh) whose action is mediated by two subclasses of receptors, namely nicotinic and muscarinic receptors. Using the visual system as a model, the aim here is to integrate and discuss the current knowledge on anatomy, ontogeny and function of the BFB cholinergic system. This signaling system represents the anatomo-functional basis of ACh action on neuronal network, neuronal plasticity and cognitive functions. Cholinergic system role on higher brain functions has received increasing attention since the first observation of A. Alzheimer (1907) reporting dramatic changes of the BFB cholinergic neuro-anatomy in one of the most devastating neUrodegenerative diseases of adult brain, i.e. Alzheirner's disease (AD). In addition to this observation, later work demonstrated its participation in deep re-arrangements of brain connectivity such as the regulation of neuronal plasticity during maturation of cortical sensory maps, in adult and aged brain.

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Available from: Luciano Domenici, Apr 01, 2014
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    • "A more intriguing possibility concerns the roles in neural plasticity and memory formation played by ACh and theta, either of which has been separately implicated in many early studies. Particularly, cholinergic transmission permits and promotes hippocampal LTP formation (Jerusalinsky et al., 1997; Segal and Auerbach, 1997; Leung et al., 2003; Doralp and Leung, 2008), and permits the reorganization of cortical sensory representation (Kilgard and Merzenich, 1998; Sachdev et al., 1998; Conner et al., 2005; Origlia et al., 2008) as well as associated behavioral memory (Bakin and Weinberger, 1996). Temporally-specific activation of cholinergic nuclei was shown to be effective in inducing such plastic changes too (Bakin and Weinberger, 1996), while temporally-mismatched activation interferes with specific memory (Winters et al., 2007). "
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