Abstract
An increase in folate catabolism has been suggested as the cause of the folate deficiency observed in many clinical conditions, including chronic anticonvulsant therapy. Previous studies have shown that the radioactive catabolites, excreted after an equilibration period of 3 d, consisted exclusively of folates that had been cleaved to produce pteridines and p-aminobenzoylglutamate, most of which was excreted as acetamidobenzoylglutamate. We have developed an experimental animal model using mice to determine the rate of catabolism of [3H]pteroylglutamate (folic acid) by the quantitative estimation of [3H]p-aminobenzoylglutamate and [3H]acetamidobenzoylglutamate in urine. Administration of diphenylhydantoin at three different doses (0.5, 20, and 50 mg/kg) significantly increased the rate of catabolism as measured by an increase in both the mean daily excretion and the cumulative excretion of these catabolites. Administration of intramuscular phenobarbitone on the other hand, did not affect the rate of catabolism, when compared with controls.
Full text
PDF







Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- A thought for the dibled driver. Lancet. 1969 Sep 6;2(7619):528–529. [PubMed] [Google Scholar]
- Barford P. A., Blair J. A., Staff F. J., Malghani M. A. The metabolism of folates in the rat: studies with 3H- and 14C-labelled folic acid in the presence and in the absence of methotrexate [proceedings]. Biochem Soc Trans. 1977;5(5):1316–1318. doi: 10.1042/bst0051316. [DOI] [PubMed] [Google Scholar]
- Baugh C. M., Krumdieck C. L. Effects of phenytoin on folic-acid conjugases in man. Lancet. 1969 Sep 6;2(7619):519–521. doi: 10.1016/s0140-6736(69)90218-9. [DOI] [PubMed] [Google Scholar]
- Bernstein L. H., Gutstein S., Weiner S., Efron G. The absorption and malabsorption of folic acid and its polyglutamates. Am J Med. 1970 May;48(5):570–579. doi: 10.1016/0002-9343(70)90006-9. [DOI] [PubMed] [Google Scholar]
- Blair J. A., Dransfield E. The urinary excretion of orally administered pteroyl-L-glutamic acid by the rat. Biochem J. 1971 Aug;123(5):907–914. doi: 10.1042/bj1230907. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chanarin I., McLean A. Origin of serum and urinary methyltetrahydrofolate in man. Some observations on the methylfolate block hypothesis in Addisonian pernicious anaemia. Clin Sci. 1967 Feb;32(1):57–67. [PubMed] [Google Scholar]
- Chantler C., Garnett E. S., Parsons V., Veall N. Glomerular filtration rate measurement in man by the single injection methods using 51Cr-EDTA. Clin Sci. 1969 Aug;37(1):169–180. [PubMed] [Google Scholar]
- Conney A. H. Pharmacological implications of microsomal enzyme induction. Pharmacol Rev. 1967 Sep;19(3):317–366. [PubMed] [Google Scholar]
- Fehling C., Jägerstad M., Lindstrand K., Westesson A. K. The effect of anticonvulsant therapy upon the absorption of folates. Clin Sci. 1973 Jun;44(6):595–600. doi: 10.1042/cs0440595. [DOI] [PubMed] [Google Scholar]
- Gerson C. D., Hepner G. W., Brown N., Cohen N., Herbert V., Janowitz H. D. Inhibition by diphenylhydantoin of folic acid absorption in man. Gastroenterology. 1972 Aug;63(2):246–251. [PubMed] [Google Scholar]
- HAWKINS C. F., MEYNELL M. J. Macrocytosis and macrocytic anaemia caused by anticonvulsant drugs. Q J Med. 1958 Jan;27(105):45–63. [PubMed] [Google Scholar]
- Houlihan C. M., Scott J. M., Boyle P. H., Weir D. G. The effect of phenytoin on the absorption of synthetic folic acid polyglutamate. Gut. 1972 Mar;13(3):189–190. doi: 10.1136/gut.13.3.189. [DOI] [PMC free article] [PubMed] [Google Scholar]
- JOHNS D. G., SPERTI S., BURGEN A. S. The metabolism of tritiated folic acid in man. J Clin Invest. 1961 Sep;40:1684–1695. doi: 10.1172/JCI104391. [DOI] [PMC free article] [PubMed] [Google Scholar]
- KLIPSTEIN F. A. SUBNORMAL SERUM FOLATE AND MACROCYTOSIS ASSOCIATED WITH ANTICONVULSANT DRUG THERAPY. Blood. 1964 Jan;23:68–86. [PubMed] [Google Scholar]
- Krumdieck C. L., Fukushima K., Fukushima T., Shiota T., Butterworth C. E., Jr A long-term study of the excretion of folate and pterins in a human subject after ingestion of 14C folic acid, with observations on the effect of diphenylhydantoin administration. Am J Clin Nutr. 1978 Jan;31(1):88–93. doi: 10.1093/ajcn/31.1.88. [DOI] [PubMed] [Google Scholar]
- Lane F., Goff P., McGuffin R., Eichner E. R., Hillman R. S. Folic acid metabolism in normal, folate deficient and alcoholic man. Br J Haematol. 1976 Nov;34(3):489–500. doi: 10.1111/j.1365-2141.1976.tb03595.x. [DOI] [PubMed] [Google Scholar]
- Latham A. N., Millbank L., Richens A., Rowe D. J. Liver enzyme induction by anticonvulsant drugs, and its relationship to disturbed calcium and folic acid metabolism. J Clin Pharmacol. 1973 Aug-Sep;13(8):337–342. doi: 10.1002/j.1552-4604.1973.tb00221.x. [DOI] [PubMed] [Google Scholar]
- Maxwell J. D., Hunter J., Stewart D. A., Ardeman S., Williams R. Folate deficiency after anticonvulsant drugs: an effect of hepatic enzyme induction? Br Med J. 1972 Jan 29;1(5795):297–299. doi: 10.1136/bmj.1.5795.297. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McLean A., Chanarin I. Urinary excretion of 5-methyl-tetrahydrofolate in man. Blood. 1966 Mar;27(3):386–388. [PubMed] [Google Scholar]
- Miller D. R. Serum folate deficiency in children receiving anticonvulsant therapy. Pediatrics. 1968 Mar;41(3):630–635. [PubMed] [Google Scholar]
- Murphy M., Keating M., Boyle P., Weir D. G., Scott J. M. The elucidation of the mechanism of folate catabolism in the rat. Biochem Biophys Res Commun. 1976 Aug 23;71(4):1017–1024. doi: 10.1016/0006-291x(76)90756-7. [DOI] [PubMed] [Google Scholar]
- Murphy M., Scott J. M. The turnover catabolism and excretion of folate administered at physiological concentrations in the rat. Biochim Biophys Acta. 1979 Apr 3;583(4):535–539. doi: 10.1016/0304-4165(79)90071-0. [DOI] [PubMed] [Google Scholar]
- Neale G. Enzyme-inducing agents and their effect on vitamin D metabolism. Front Gastrointest Res. 1976;2:32–70. doi: 10.1159/000398593. [DOI] [PubMed] [Google Scholar]
- Perry J., Chanarin I. Observations on folate absorption with particular reference to folate polyglutamate and possible inhibitors to its absorption. Gut. 1972 Jul;13(7):544–550. doi: 10.1136/gut.13.7.544. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reed B., Weir D., Scott J. The occurrence of folate-derived pteridines in rat liver. Clin Sci Mol Med. 1978 Apr;54(4):355–360. doi: 10.1042/cs0540355. [DOI] [PubMed] [Google Scholar]
- Reynolds E. H. Chronic antiepileptic toxicity: a review. Epilepsia. 1975 Jun;16(2):319–352. doi: 10.1111/j.1528-1157.1975.tb06062.x. [DOI] [PubMed] [Google Scholar]
- Richens A., Waters A. H. Acute effect of phenytoin on serum folate concentration. Br J Pharmacol. 1971 Feb;41(2):414P–415P. [PMC free article] [PubMed] [Google Scholar]
- Rosenberg I. H., Godwin H. A., Streiff R. R., Castle W. B. Impairment of intestinal deconjugation of dietary folate. A possible explanation of megaloblastic anaemia associated with phenytoin therapy. Lancet. 1968 Sep 7;2(7567):530–532. doi: 10.1016/s0140-6736(68)92405-7. [DOI] [PubMed] [Google Scholar]
- Scott J. M., Weir D. G. Folate composition, synthesis and function in natural materials. Clin Haematol. 1976 Oct;5(3):547–568. [PubMed] [Google Scholar]
- Shane B., Watson J. E., Stokstad E. L. Uptake and metabolism of [3H]folate by normal and by vitamin B-12- and methionine-deficient rats. Biochim Biophys Acta. 1977 Mar 29;497(1):241–252. doi: 10.1016/0304-4165(77)90157-x. [DOI] [PubMed] [Google Scholar]
- Zakrzewski S. F., Evans E. A., Phillips R. F. On the specificity of labeling in tritiated folic acid. Anal Biochem. 1970 Jul;36(1):197–206. doi: 10.1016/0003-2697(70)90348-9. [DOI] [PubMed] [Google Scholar]
