title: Significance of the degree of synaptic Zn²⁺ signaling in cognition.
abstract: Zinc is a trace nutrient for the brain and a signal factor to serve for brain function. A portion of zinc is released from glutamatergic (zincergic) neuron terminals in the brain. Synaptic Zn(2+) signaling is involved in synaptic plasticity such as long-term potentiaion (LTP), which is a cellular mechanism of memory. The block and/or loss of synaptic Zn(2+) signaling in the hippocampus and amygdala with Zn(2+) chelators affect cognition, while the role of synaptic Zn(2+) signal is poorly understood, because zinc-binding proteins are great in number and multi-functional. Chronic zinc deficiency also affects cognition and cognitive decline induced by zinc deficiency might be associated with the increase in plasma glucocorticoid rather than the decrease in synaptic Zn(2+) signaling. On the other hand, excess glutamatergic (zincergic) neuron activity induces excess influx of extracellular Zn(2+) into hippocampal neurons, followed by cognitive decline. Intracellular Zn(2+) dynamics, which is linked to presynaptic glutamate release, is critical for LTP and cognitive performance. This paper deals with insight into cognition from zinc as a nutrient and signal factor.
authors.affiliation: Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan. takedaa@u-shizuoka-ken.ac.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takeda
authors.affiliation: Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan.
authors.forename: Haruna
authors.initials: H
authors.lastname: Tamano
mesh_terms: D000818:Animals; D003071:Cognition / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D006706:Homeostasis; D006801:Humans; D009435:Synaptic Transmission; D015032:Zinc / Q000172:deficiency / Q000502:physiology*
chemical_list: D015032:Zinc
keywords: Cognition; Hippocampus; Homeostasis; Signaling; Zinc; Zinc deficiency