Elsevier

Hearing Research

Volume 36, Issues 2–3, November 1988, Pages 203-211
Hearing Research

Zinc-containing fiber systems in the cochlear nuclei of the rat and mouse

https://doi.org/10.1016/0378-5955(88)90062-7Get rights and content

Abstract

Zinc-containing neurons are cells which sequester zinc in the vesicles of their axonal boutons; such zinc-containing fiber systems have been previously shown to innervate many limbic and cerebrocortical brain regions. The present study of rats and mice shows that zinc-containing axons also innervate the cochlear nuclei, forming two morphologically-distinct projection systems. One zinc-containing pathway innervates the molecular stratum of the dorsal nucleus, supplying a diffuse, even band of neuropil staining throughout the stratum. The other pathway projects sparsely to the various small cell (granule cell) regions of the nuclei where the zinc-positive elements form scattered clusters and threads of bouton-like puncta amidst the granule neuron somata. Preliminary observations indicate that the pattern is the same in the cat as in the rat and mouse.

References (38)

  • S.Y. Assaf et al.

    Release of endogenous Zn2+ from brain tissue during activity

    Nature

    (1984)
  • I.L. Crawford

    Relationship of glutamic acid and zinc to kindling of the rat amygdala: Afferent transmitter systems and excitability in a model of epilepsy

  • G. Danscher

    Histochemical demonstration of heavy metals. A revised version of the sulphide silver method suitable for both light and electronmicroscopy

    Histochemistry

    (1981)
  • G. Danscher

    Exogenous selenium in the brain. A histochemical technique for light and electron microscopical localization of catalytic selenium bonds

    Histochemistry

    (1982)
  • G. Danscher

    Do the Timm silver-sulphide and the selenium method demonstrate zinc in the brain?

  • G. Danscher

    Similarities and differences in the localization of metals in rat brains after treatment with sodium sulphide and sodium selenide

  • G. Danscher et al.

    The dithizone, Timm's sulphide silver and the selenium methods demonstrate a chelatable pool of zinc in CNS

    Histochemistry

    (1985)
  • R.M. Epand et al.

    Mechanism of action of diabetogenic zinc-chelating agents

  • C.J. Frederickson

    Neurobiology of zinc and zinc containing neurons

    Int. Rev. Neurobiol.

    (1988)
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