Calcium transporters and gene expression and absorption of calcium in pigs

J. C. González-Vega, H. H. Stein

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

Calcium (Ca) absorption occurs by two mechanisms, nonsaturable paracellular absorption and saturable transcellular absorption. The activity of these mechanisms depends on the concentration of Ca in the diet. At high dietary Ca concentration, the nonsaturable mechanism is more active, whereas at low dietary Ca concentration, the saturable mechanism is more involved. The saturable mechanism is vitamin-D dependent, because the expression of genes related to the transcellular transport may be influenced by the active form of vitamin D. Increasing dietary Ca decreases the mRNA expression of transient receptor potential cation channel, subfamily V, member 6 (TRPV6), which is used for absorption of Ca into the enterocytes in the jejunum. However, this does not result in less absorption of Ca, because as dietary Ca increases, an increased proportion of Ca is absorbed via the paracellular route in the small intestine and the total percentage of Ca that is absorbed is almost constant regardless of dietary Ca concentration. High concentrations of dietary Ca will also reduce the mRNA expression in the kidneys of TRPV6, TRPV5, S100 calcium binding protein G, and calbindin 1, but because there is no paracellular reabsorption of Ca in the kidneys excretion of Ca in the urine is increased as dietary Ca concentration increases. As a consequence, body Ca concentrations are primarily regulated in the kidneys.

Original languageEnglish (US)
Title of host publicationPhytate Destruction - Consequences for Precision Animal Nutrition
PublisherWageningen Academic Publishers
Pages217-224
Number of pages8
ISBN (Electronic)9789086868360
ISBN (Print)9789086862900
DOIs
StatePublished - Jan 1 2016

Keywords

  • Calbindin
  • Calcium channels
  • Paracellular absorption
  • Transcellular absorption
  • Vitamin D receptor

ASJC Scopus subject areas

  • General Engineering
  • General Agricultural and Biological Sciences

Fingerprint

Dive into the research topics of 'Calcium transporters and gene expression and absorption of calcium in pigs'. Together they form a unique fingerprint.

Cite this