Zinc transporter 3 immunohistochemical tracing of sprouting mossy fibres

Neurochem Int. 2008 Jun;52(7):1305-9. doi: 10.1016/j.neuint.2008.02.008. Epub 2008 Mar 6.

Abstract

Zinc transporter 3 (ZNT3) has been shown to transport zinc ions from the cytosol into presynaptic vesicles in the mammalian brain. Several studies have stated that the zinc ion containing synaptic vesicles of zinc-enriched neurons (ZEN) are loaded with ZNT3 proteins in their membranes. This fact makes it possible to trace sprouting mossy fibres in the temporal lobe epileptic hippocampus. In the present study, we examined the expression and distribution patterns of ZNT3 protein and chelatable zinc ions in the mouse hippocampus after pilocarpine treatment. Our results demonstrate that both ZNT3 immunostaining and autometallography reveal identical patterns of sprouting mossy fibres in the inner molecular layer in the mouse hippocampus. Using ZNT3 immuno-electron microscopic analysis we confirmed the presence of ectopic mossy fibre terminals in the inner molecular layer and found additionally by immuno-blotting a significant increase of ZNT3 in the pilocarpine-treated mouse hippocampi compared to age-matched controls. The increase of ZNT3 after pilocarpine treatment was time-dependent. The results support the notion that ZNT3 immunohistochemistry provides an excellent tool for tracing sprouting of ZEN terminals. The progressive increase of ZNT3 immunostaining in the temporal lobe epileptic hippocampus may relate to the increased levels of vesicular zinc ions during seizure.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • Carrier Proteins / metabolism*
  • Cation Transport Proteins
  • Epilepsy / chemically induced
  • Epilepsy / pathology
  • Immunohistochemistry
  • Male
  • Membrane Proteins / metabolism*
  • Membrane Transport Proteins
  • Mice
  • Mossy Fibers, Hippocampal / metabolism*
  • Mossy Fibers, Hippocampal / ultrastructure
  • Muscarinic Agonists / pharmacology
  • Pilocarpine / pharmacology
  • Presynaptic Terminals / metabolism
  • Presynaptic Terminals / ultrastructure
  • Zinc / metabolism

Substances

  • Carrier Proteins
  • Cation Transport Proteins
  • Membrane Proteins
  • Membrane Transport Proteins
  • Muscarinic Agonists
  • Slc30a3 protein, mouse
  • Pilocarpine
  • Zinc