Biosynthesis of ubiquinone and ubichromenol in vitamin A-deficient rats

• Published in: Biochimica et biophysica acta Vol. 115; no. 2; pp. 294 - 305
• Main Authors: Joshi, V.C., Ramasarma, T.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 28.02.1966
• Subjects: Animals; Benzopyrans - biosynthesis; In Vitro Techniques; Intestinal Mucosa - metabolism; Kidney - metabolism; Liver - metabolism; Mevalonic Acid - metabolism; Rats; Ubiquinone - biosynthesis; Vitamin A Deficiency - metabolism
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/0304-4165(66)90428-4

1. 1. The concentrations of ubiquinone and ubichromenol increased in the livers, but not in the intestines and kidneys, of rats maintained on a diet deficient in vitamin A. 2. 2. After short time intervals ( e.g. 2 h) following administration of the tracer, incorporation of [2- 14C]mevalonate into ubiquinone and ubichromenol in livers of vitamin A-deficient rats was lower than for normal animals; this was in contrast to later times ( e.g. 72 h) when it was higher. 3. 3. The “newly synthesized” ubiquinone in livers of vitamin A-deficient rats was distributed in all the cell fractions without specific localization. 4. 4. Absorbed exogenous [ 14C]ubiquinone and [ 14C]ubichromenol were retained in the livers of vitamin A-deficient rats to a larger extent and for a longer time than in the normal animals. 5. 5. The results suggest that the accumulation of ubiquinone and ubichromenol in the livers of vitamin A-deficient rats is due to lowered catabolism and not to increased rate of synthesis.