Excess vitamin A and the metabolism of carbohydrates: variation of enzyme activities in gingiva of rats submitted to excess vitamin A, vitamin A plus cortisol and vitamin A plus ascorbic acid

Acta Vitaminol Enzymol. 1983;5(4):205-12.


The effect of 1 to 5 doses of 15,000 I.U. of vitamin A on some enzymes of the carbohydrate metabolism in gingival tissue from rats was studied. Vitamin A feeding resulted in a significant increase in the activities of hexokinase and pyruvate kinase with the different doses tested. A reduction in the activity of phosphofructokinase was observed with 2 and 4 doses. The administration of ascorbic acid along with vitamin A, did not prevent the effects of vitamin A on the activities of the enzymes studied. The data on the enzyme activities in the groups simultaneously fed on vitamin A and cortisol may indicate an additive effect of these compounds.

MeSH terms

  • Animals
  • Ascorbic Acid / pharmacology*
  • Carbohydrate Metabolism*
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Gingiva / enzymology*
  • Hexokinase / metabolism
  • Hydrocortisone / pharmacology*
  • Male
  • Pyruvate Kinase / metabolism
  • Rats
  • Rats, Inbred Strains
  • Vitamin A / pharmacology*


  • Vitamin A
  • Hexokinase
  • Pyruvate Kinase
  • Ascorbic Acid
  • Hydrocortisone