The retina rapidly incorporates ingested C20-D₃-vitamin A in a swine model

Mol Vis. 2013 Jul 25;19:1677-83. Print 2013.


Purpose: To determine how the retina uses vitamin A for vision, we studied the flux of oral vitamin A into and out of the swine retina.

Methods: We administered labeled vitamin A to swine daily for 30 days and measured the percent of the labeled vitamin A to native unlabeled vitamin A in the retinal epithelium, neuroretina, plasma, liver, lung, and kidney.

Results: We show that during normal vitamin A homeostasis, the retina rapidly assimilates newly ingested dietary vitamin A, which replaces native vitamin A. Retinal vitamin A is turned over faster than previously thought. Provitamin A carotenoids do not significantly contribute to retinal vitamin A pools when consuming diets adequate in vitamin A.

Conclusions: Fast vitamin A turnover in the retina has direct implications for emerging therapies to prevent major forms of blindness based on controlling the concentrations of retinal vitamin A.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorption / drug effects
  • Animals
  • Deuterium / metabolism*
  • Male
  • Models, Animal
  • Models, Biological
  • Retina / drug effects*
  • Retina / metabolism*
  • Sus scrofa
  • Vitamin A / pharmacology*


  • Vitamin A
  • Deuterium