Localization of ZnT7 and zinc ions in mouse retina--immunohistochemistry and selenium autometallography

Brain Res Bull. 2006 Dec 11;71(1-3):91-6. doi: 10.1016/j.brainresbull.2006.08.002. Epub 2006 Aug 31.

Abstract

Zinc transporter 7 (ZnT7, Slc30a7), a member of the Slc30 family, is involved in mobilizing zinc ions from the cytoplasm into the Golgi apparatus. In the present study, we examined the distribution and localization of ZnT7 and the labile zinc ions in the mouse retina using immunohistochemistry and in vivo zinc-selenium autometallography (ZnSe(AMG)). Our results showed that ZnT7 is abundantly expressed in the ganglion cells and pigment epithelial cells of the mouse retina. ZnT7 is also expressed in the amacrine cells and the layer of optic fibers of the mouse retina, but to a lesser extent. Weak staining of ZnT7 was detected in the inner plexiform layer, outer plexiform layer, and outer segment of the photoreceptors. However, ZnT7 was not detected in the outer nuclear layer and inner segment of the photoreceptors. A high level of labile zinc pool was detected in the pigment epithelial cells, the inner segment of the photoreceptors, and the marginal region of the inner nuclear layer. Less amount of labile zinc ions were detected in the ganglion cells of the retina. These observations strongly suggest that ZnT7 may play critical roles in retinal zinc homeostasis and that chelatable zinc pools may have multiple functions in the retina.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amacrine Cells / cytology
  • Amacrine Cells / metabolism
  • Animals
  • Autoradiography / methods
  • Cation Transport Proteins / metabolism*
  • Homeostasis / physiology
  • Immunohistochemistry
  • Male
  • Mice
  • Neurons / cytology
  • Neurons / metabolism*
  • Photoreceptor Cells, Vertebrate / cytology
  • Photoreceptor Cells, Vertebrate / metabolism
  • Pigment Epithelium of Eye / cytology
  • Pigment Epithelium of Eye / metabolism
  • Retina / cytology
  • Retina / metabolism*
  • Retinal Ganglion Cells / cytology
  • Retinal Ganglion Cells / metabolism
  • Selenium
  • Vision, Ocular / physiology
  • Zinc / metabolism*

Substances

  • Cation Transport Proteins
  • ZnT7 protein, mouse
  • Selenium
  • Zinc