Abstract
Ascorbic acid levels in plasma and leucocytes and urinary excretion of tyrosyl derivatives (TD) were determined in 11 normal, 18 preterm, and 4 small-for-dates infants. Concentrations of ascorbic acid in both plasma and leucocytes were found to be similar in the 3 groups. There was no difference in the basal levels of TD between normal and small-for-dates infants, but preterms showed higher basal excretion of TD than the other two groups. After protein load the excretion of TD was higher than the basal level in preterms. It was concluded that the altered metabolism of tyrosine observed in preterms is not the result of poor ascorbic acid status; and that tyrosine metabolism is influenced by the period of gestation rather than the body weight of the infant.
Full text
PDF


Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- DENSON K. W., BOWERS E. F. The determination of ascorbic acid in white blood cells. A comparison of W.B.C. ascorbic acid and phenolic acid excretion in elderly patients. Clin Sci. 1961 Oct;21:157–162. [PubMed] [Google Scholar]
- HUISMAN T. H., JONXIS J. H. Some investigations on the metabolism of phenylalanine and tyrosine in children with vitamin C deficiency. Arch Dis Child. 1957 Apr;32(162):77–81. doi: 10.1136/adc.32.162.77. [DOI] [PMC free article] [PubMed] [Google Scholar]
- KRETCHMER N., LEVINE S. Z., MCNAMARA H., BARNETT H. L. Certain aspects of tyrosine metabolism in the young. I. The development of the tyrosine oxidizing system in human liver. J Clin Invest. 1956 Feb;35(2):236–244. doi: 10.1172/JCI103268. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Levine S. Z., Gordon H. H., Marples E. A DEFECT IN THE METABOLISM OF TYROSINE AND PHENYLALANINE IN PREMATURE INFANTS. II. SPONTANEOUS OCCURRENCE AND ERADICATION BY VITAMIN C. J Clin Invest. 1941 Mar;20(2):209–219. doi: 10.1172/JCI101213. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Levine S. Z., Marples E., Gordon H. H. A DEFECT IN THE METABOLISM OF AROMATIC AMINO ACIDS IN PREMATURE INFANTS: THE ROLE OF VITAMIN C. Science. 1939 Dec 29;90(2348):620–621. doi: 10.1126/science.90.2348.620. [DOI] [PubMed] [Google Scholar]
- MATHEWS J., PARTINGTON M. W. THE PLASMA TYROSINE LEVELS OF PREMATURE BABIES. Arch Dis Child. 1964 Aug;39:371–378. doi: 10.1136/adc.39.206.371. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Medes G. A new error of tyrosine metabolism: tyrosinosis. The intermediary metabolism of tyrosine and phenylalanine. Biochem J. 1932;26(4):917–940. doi: 10.1042/bj0260917. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morris J. E., Harpur E. R., Goldbloom A. THE METABOLISM OF l-TYROSINE IN INFANTILE SCURVY. J Clin Invest. 1950 Mar;29(3):325–335. doi: 10.1172/JCI102261. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Prasad L. S., Sinha K. P., Sen D. K. Tyrosinemia and tyrosinuria in low birth weight infants in India. Indian Pediatr. 1972 Nov;9(11):703–706. [PubMed] [Google Scholar]
- Rizzardini M., Abeliuk P. Tyrosinemia and tyrosinuria in low-birth-weight infants. A new criterion to assess maturity at birth. Am J Dis Child. 1971 Feb;121(2):182–185. doi: 10.1001/archpedi.1971.02100130136019. [DOI] [PubMed] [Google Scholar]
