Localization of Metallothionein in the Mammalian Central Nervous System

Abstract

This review concerns the immunohistochemical localization of metallothionein (MT), a metal-binding protein, in the mammalian central nervous system (CNS). Expression of MT in the mammalian CNS is abundant. In the mouse brain, MT expression is found in some glial cells, whereas in the adult rat brain immunoreactivity varies from no expression at all to abundant reactivity throughout the whole brain. In primates and humans, MT expression is mainly found in astrocytes. Thus, MT expression in the mammalian CNS is found in the pia-arachnoid, ependymal cells and astrocytes. Cells expressing MTs can, in this way, supply essential metals to neurons and may protect neurons against toxic ions.

Effect of Ethanol on Brain Metallothionein in Transgenic Mice

“…It is proposed that increased LPO might result in tissue injuries which release cytokines from tissues, and these cytokines can induce MT synthesis (Sato and Bremner, 1993;Shibuya et al, 1995). Recent studies suggest that because MT is present in astrocytes in the central nervous system (Blaauwgeers et al, 1994;Carrasco et al, 1998;Nishimura et al, 1992), astrocytes may pla$ an important role in protecting against oxidative stress (kschner, 1997, 1998).…”

Peculiarities of the Molecular Structure and Functions of Metallothioneins in the Central Nervous System

“…The main source of MTs in the brain are astrocytes, although this protein was also found in the epithelium of the choroid plexus of the nerves, endothelium, and meningeal cells. Data with respect to the amount of MTs in neurons are ambiguous, although it was reported that the MT-І+ІІ complex provides the defense of neurons under culture conditions [21,22].…”

“…The statement "Detoxication with respect to heavy metals (Cd, Hg, Ag, Au, and Pt), which is mediated by the functioning of hematoencephalic and hematoliquor barriers is the main function of MTs" is at present believed to be well established [11,22].…”

Amyloid neurotoxicity is attenuated by metallothionein: dual mechanisms at work

“…2002). In the CNS, the MT‐I and II subtypes are mainly expressed in astrocytes and microglia (Blaauwgeers et al. 1994; Hidalgo et al.…”

“…Metallothioneins (MTs) are low molecular weight (6-7 kDa), cysteine-rich (30% of the amino acid contents), and ubiquitous stress proteins (Coyle et al 2002). In the CNS, the MT-I and II subtypes are mainly expressed in astrocytes and microglia (Blaauwgeers et al 1994;Hidalgo et al 2001), while the MT-III subtype is predominantly expressed in neuronal cells (Masters et al 1994). The MT-IV subtype has been found in stratified epithelia .…”