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Daily Rhythms in the Concentrations of Various Amino Acids in Human Plasma
Abstract
Blood was collected at intervals during a 24-hour period from 23 healthy male volunteers on diets containing various amounts of protein; the plasma was assayed for 16 amino acids. Among subjects receiving 0.71 or 1.5 gm of protein per kilogram of body weight, the concentrations of tyrosine, phenylalanine and tryptophan tended to be lowest at 2:00 and highest at or after 10:30 a.m. Volunteers given a diet containing less than 0.04 gm of protein per kilogram showed similar fluctuations in the concentrations of the above amino acids and methionine, but peak plasma levels were observed somewhat earlier in the morning. All the amino acids studied showed some tendency to vary with time of day. Tyrosine, tryptophan, phenylalanine, methionine, cysteine and isoleucine underwent the greatest per cent changes; the amino acids whose plasma concentrations were highest (that is, alanine, glycine and glutamic acid) showed the least tendency to vary.
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Citations
Cited by
Brain Serotonin Content: Physiological Dependence on Plasma Tryptophan Levels
Fernstrom, J. D., & Wurtman, R. J. (1971) · Science · doi:10.1126/science.173.3992.149 · Cited by 1,016
Self-citationPlasma Amino Acid Levels and Insulin Secretion in Obesity
Felig, P., Marliss, E., & Cahill, G. F. (1969) · New England Journal of Medicine · doi:10.1056/nejm196910092811503 · Cited by 812
Ang, J. E., Revell, V., Mann, A., Mäntele, S., Otway, D. T., Johnston, J. D., Thumser, A. E., Skene, D. J., & Raynaud, F. (2012) · Chronobiology International · doi:10.3109/07420528.2012.699122 · Cited by 138
Amino Acids, Peptides, and Proteins
Dietzen, D. J. (2018) · Principles and Applications of Molecular Diagnostics · doi:10.1016/b978-0-12-816061-9.00013-8 · Cited by 82
Nutt, J. G., Woodward, W. R., Carter, J. H., & Trotman, T. L. (1989) · Journal of Neurology, Neurosurgery & Psychiatry · doi:10.1136/jnnp.52.4.481 · Cited by 49
Metadata
- Authors
- Wurtman, R. J., Rose, C. M., Chou, C., & Larin, F. F.
- Venue
- New England Journal of Medicine
- Publisher
- Massachusetts Medical Society
- Published
- 1968-07-25
- Volume
- 279
- Issue
- 4
- Pages
- 171-175
- ISSN
- 0028-4793 (ISSN-L)
- 1533-4406
- OpenAlex
- W1966343701
- Cited by
- 192
- References
- 0
- FWCI
- 8.96
- Type
- journal article
- Language
- en
- Open access
- closed
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- Wurtman, R. J., Rose, C. M., Chou, C., & Larin, F. F. (1968). Daily Rhythms in the Concentrations of Various Amino Acids in Human Plasma. New England Journal of Medicine. https://doi.org/10.1056/nejm196807252790401
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