Mechanisms of zinc uptake in gills of freshwater rainbow trout: Interplay with calcium transport

Christer Hogstrand, Pieter M. Verbost, Sjoerd E. Wendelaar Bonga, Chris M. Wood

Research output: Contribution to journalArticle

132 Scopus citations

Abstract

The uptake mechanism of Zn2+ through the gill epithelium of freshwater rainbow trout was investigated both in intact animals and in isolated basolateral membranes. Involvement of the apical Ca2+ uptake sites in Zn2+ uptake was examined in vivo by pharmacological manipulation of the apical Ca2+ permeability. The apical entries of Ca2+ and Zn2+, but not Na+ and Cl, were inhibited by addition of La to the water. Addition of 1.0 μM La reduced the influxes of Ca2+ and Zn2+ to 22 ± 3 and 53 ± 7% (means ± SE) of the control value, respectively. Injection of CaCl2 also reduced the branchial influxes of Ca2+ and Zn2+. This treatment decreased the influx of Ca2+ to 45 ± 4% of the control level and the Zn2+ influx to 68 ± 5%. These results strongly imply that Zn2+ passes across the apical membrane of the chloride cells of the gills via the same pathway as Ca2+. The presence of an active basolateral transporter for Zn2+ was investigated in vitro on isolated basolateral membranes. There was no ATP- dependent or Na+-gradient driven transport of Zn2+ at physiological Zn2+ activities. The same system was used to study potential effects of Zn2+ on the basolateral Ca2+-adenosinetriphosphatase. Zn2+ was found to be a potent blocker of this transporter, causing a mixed inhibitory effect on the ATP-driven Ca2+ transport at a free Zn2+ activity of 100 pM.

Original languageEnglish (US)
Pages (from-to)R1141-R1147
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume270
Issue number5 39-5
DOIs
StatePublished - 1996

Keywords

  • Ca channel
  • Ca- adenosinetriphosphatase
  • chloride cells
  • inhibition
  • ionocytes
  • lanthanum
  • regulation
  • stanniocalcin

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Mechanisms of zinc uptake in gills of freshwater rainbow trout: Interplay with calcium transport'. Together they form a unique fingerprint.

  • Cite this