Extracellular glutathione peroxidase (Gpx3) binds specifically to basement membranes of mouse renal cortex tubule cells.


Journal Article

Glutathione peroxidase-3 (Gpx3), also known as plasma or extracellular glutathione peroxidase, is a selenoprotein secreted primarily by kidney proximal convoluted tubule cells. In this study Gpx3(-/-) mice have been produced and immunocytochemical techniques have been developed to investigate Gpx3 metabolism. Gpx3(-/-) mice maintained the same whole-body content and urinary excretion of selenium as did Gpx3(+/+) mice. They tolerated selenium deficiency without observable ill effects. The simultaneous knockout of Gpx3 and selenoprotein P revealed that these two selenoproteins account for >97% of plasma selenium. Immunocytochemistry experiments demonstrated that Gpx3 binds selectively, both in vivo and in vitro, to basement membranes of renal cortical proximal and distal convoluted tubules. Based on calculations using selenium content, the kidney pool of Gpx3 is over twice as large as the plasma pool. These data indicate that Gpx3 does not serve in the regulation of selenium metabolism. The specific binding of a large pool of Gpx3 to basement membranes in the kidney cortex strongly suggests a need for glutathione peroxidase activity in the cortical peritubular space.

Full Text

Duke Authors

Cited Authors

  • Olson, GE; Whitin, JC; Hill, KE; Winfrey, VP; Motley, AK; Austin, LM; Deal, J; Cohen, HJ; Burk, RF

Published Date

  • May 2010

Published In

Volume / Issue

  • 298 / 5

Start / End Page

  • F1244 - F1253

PubMed ID

  • 20015939

Pubmed Central ID

  • 20015939

Electronic International Standard Serial Number (EISSN)

  • 1522-1466

International Standard Serial Number (ISSN)

  • 1931-857X

Digital Object Identifier (DOI)

  • 10.1152/ajprenal.00662.2009


  • eng