• IMA sites
  • IMAJ services
  • IMA journals
  • Follow us
  • Alternate Text Alternate Text
עמוד בית
Sun, 08.12.24

Search results


February 2010
B. Weiss, I. Barshack, N. Onaca, I. Goldberg, Z. Berkovich, E. Melzer, A. Jonas and R. Reifen

Background: Vitamin A and its derivative retinoic acid regulate various aspects of cell behavior as growth, differentiation, and proliferation. Retinoic acid derivatives have been suggested to play a role in processes such as hepatic regeneration and fibrosis.

Objectives: To evaluate the influence of vitamin A on rat liver epithelial cell proliferation.

Methods: We performed common bile duct ligation in rats that had been subjected to differing vitamin A diets and compared their livers to control rats. Proliferation, apoptosis, and retinoic acid receptors were evaluated by histology and immunohistochemistry in bile duct cells and hepatocytes.

Results: Vitamin A deficiency was found to be associated with enhanced proliferation of bile duct epithelial cells following CBD[1] ligation. The proliferation was manifested by increased numbers of ducts, by aberrant extended ductal morphology, and by elevated numbers of nuclei expressing the proliferation marker Ki67. The amount of vitamin A in the rat diet did not affect detectably ductal cell apoptosis. We observed up-regulated expression of the retinoid X receptor-alpha in the biliary epithelium of vitamin A-deficient rats that had undergone CBD ligation, but not in vitamin A-sufficient rats.

Conclusions: We speculate that the mechanism underlying the ductal proliferation response involves differential expression of RXR[2]-alpha. Our observations suggest that deficiency of vitamin A may exacerbate cholestasis, due to excessive intrahepatic bile duct proliferation.






[1] CBD = common bile duct



[2] RXR = retinoid X receptor


December 2001
Orith Portnoy, MD, Gabriela Gayer, MD, Nicholas Onaca, MD, Eitan Heldenberg, MD and Sara Apter, MD
Legal Disclaimer: The information contained in this website is provided for informational purposes only, and should not be construed as legal or medical advice on any matter.
The IMA is not responsible for and expressly disclaims liability for damages of any kind arising from the use of or reliance on information contained within the site.
© All rights to information on this site are reserved and are the property of the Israeli Medical Association. Privacy policy

2 Twin Towers, 35 Jabotinsky, POB 4292, Ramat Gan 5251108 Israel