Article

The cholinergic system and hippocampal plasticity

School of Medical Sciences, College of Life Sciences and Medicine, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
Behavioural brain research (Impact Factor: 3.03). 12/2010; 221(2):505-14. DOI: 10.1016/j.bbr.2010.11.037
Source: PubMed

ABSTRACT

Acetylcholine is an essential excitatory neurotransmitter in the central nervous system and undertakes a vital role in cognitive function. Consequently, there is ample evidence to suggest the involvement of both nicotinic and muscarinic acetylcholine receptors in the modulation of synaptic plasticity, which is believed to be the molecular correlate of learning and memory. In the hippocampus in particular, multiple subtypes of both nicotinic and muscarinic receptors are present at presynaptic and postsynaptic loci of both principal neurons and inhibitory interneurons, where they exert profound bi-directional influences on synaptic transmission. Further evidence points to a role for cholinergic activation in the induction and maintenance of synaptic plasticity, and key influences on hippocampal network oscillations. The present review examines these multiple roles of acetylcholine in hippocampal plasticity.

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    • "This yielded an interpretation that dopaminergic neurons encode the " actual minus predicted reward " (Schultz, 2002). Acetylcholine is necessary to induce plasticity in sensory cortices (Gu, 2002) and hippocampus (Drever et al., 2011) as shown in a variety of paradigms including sensory map remodeling in auditory cortex (Kilgard and Merzenich, 1998;Ma and Suga, 2005) or inhibitory avoidance training (Mitsushima et al., 2013). Similarly, noradrenaline and serotonin play a permissive and facilitatory role for the induction of plasticity (Seidenbacher et al., 1997;Gu, 2002; Tully and Bolshakov, 2010;Bergado et al., 2011). "
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    Preview · Article · Jan 2016 · Frontiers in Neural Circuits
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    • "). Activation of each type of nAChR in glutamatergic neurons enhances post-synaptic responses and cellular plasticity (Drever et al., 2011). Rodent studies have shown that α7 nAChRs on inhibitory GABAergic (gamma-aminobutyric acid) interneurons are essential for normal auditory gating (Alkondon et al., 2000), and also that reduced receptor expression deficits could be partially ameliorated by agonism of the receptor (Stevens et al., 1998). "
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    • "Metab Brain Dis ChAT expression but did not show significant effect against AchE level. The diverse function of (M1) AchR and its occurrence in the hippocampus, suggests that (M1) AchR play a key role in learning and memory (Drever et al. 2011) and is known to transiently enhance long-term potentiation resulting in neurocognitive improvement (Anisuzzaman et al. 2013). Administration of selective (M1) AchR antagonists induces spatial memory deficit (Hunter and Roberts 1988). "
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