Hostname: page-component-8448b6f56d-qsmjn Total loading time: 0 Render date: 2024-04-24T01:46:34.376Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of leucine on intestinal absorption of tryptophan in rats

Published online by Cambridge University Press:  24 July 2007

Chisae Umezawa ,
Yuko Maeda ,
Kanji Haba ,
Mariko Shin  and
Keiji Sano
Chisae Umezawa
Affiliation:
School of Pharmacy, Kobe-Gakuin University, Nishi-ku, Kobe 673, Japan
Yuko Maeda
Affiliation:
School of Pharmacy, Kobe-Gakuin University, Nishi-ku, Kobe 673, Japan
Kanji Haba
Affiliation:
School of Pharmacy, Kobe-Gakuin University, Nishi-ku, Kobe 673, Japan
Mariko Shin
Affiliation:
School of Pharmacy, Kobe-Gakuin University, Nishi-ku, Kobe 673, Japan
Keiji Sano
Affiliation:
School of Pharmacy, Kobe-Gakuin University, Nishi-ku, Kobe 673, Japan
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. To elucidate the causal relation between leucine and the lowering of hepatic NAD content of rats fed on a leucine-excessive diet (Yamada et al. 1979), the effect of leucine on intestinal absorption of tryptophan was investigated.

2. Co-administration of [3H]tryptophan and leucine, with leucine at ten times the level of tryptophan, delayed absorption of L-[side chain 2,3-3H]tryptophan from the digestive tract and incorporation of [3H]tryptophan into portal blood, the liver and a protein fraction of the liver. After 120 min, more than 95% of tryptophan was absorbed whether [3H]tryptophan was administered with or without leucine.

3. Co-administration of a mixture of ten essential amino acids, in proportions simulating casein, with [3H]tryptophan markedly delayed absorption of tryptophan from the digestive tract. The addition of supplementary leucine to the amino acid mixture, however, caused no further delay.

4. In rats prefed a leucine-excessive diet for 1 week [3H]tryptophan was absorbed at the same rate as in rats fed on a control diet.

5. The results indicate that competition between tryptophan and leucine for intestinal absorption did not cause lowering of hepatic NAD.

Type
Papers on General Nutrition
Information
British Journal of Nutrition , Volume 54 , Issue 3 , November 1985 , pp. 695 - 703
Copyright
Copyright © The Nutrition Society 1985

References

Christensen, H. N. (1984 a). Biochimica et Biophysica Acta 779, 255–269.Google Scholar
Christensen, H. N. (1984 b). Nutrition Review 42, 237–242.Google Scholar
Fujii, K. (1979). Osaka Ika Daigaku Zasshi 38, 32–52.Google Scholar
Magboul, B. I. & Bender, D. A. (1983). British Journal of Nutrition 49, 321–329.Google Scholar
Sakakibara, S., Fujii, K., Nasu, S., Imai, H., Yamaguchi, K. & Ueda, I. (1982). Journal of Nutrition 112, 1688–1695.Google Scholar
Shotwell, M. A., Kilberg, M. S. & Oxender, D. L. (1983). Biochimica et Biophysica Acta 737, 267–284.Google Scholar
Shotwell, M. A. & Oxender, D. L. (1983). Trends in Biochemical Science 8, 314–316.Google Scholar
Tannous, R. I., Rogers, Q. R. & Harper, A. E. (1966). Archives of Biochemistry and Biophysics 113, 356–361.Google Scholar
Yamada, O., Shin, M., Sano, K. & Umezawa, C. (1979). International Journal of Vitamin and Nutrition Research 49, 376–385.Google Scholar
Yamada, O., Shin, M., Sano, K. & Umezawa, C. (1983 a). International Journal of Vitamin and Nutrition Research 53, 184–191.Google Scholar
Yamada, O., Shin, M., Sano, K. & Umezawa, C. (1983 b). International Journal of Vitamin and Nutrition Research 53, 192–198.Google Scholar