N-acetyl-L-tyrosine and N-acetyl-L-cysteine as tyrosine and cysteine precursors during intravenous infusion in humans.

Article Details

Citation

Magnusson I, Ekman L, Wangdahl M, Wahren J

N-acetyl-L-tyrosine and N-acetyl-L-cysteine as tyrosine and cysteine precursors during intravenous infusion in humans.

Metabolism. 1989 Oct;38(10):957-61.

PubMed ID
2507878 [ View in PubMed
]
Abstract

The usefulness of N-acetyl-L-tyrosine (NAT) and N-acetyl-L-cysteine (NAC) as tyrosine and cysteine precursors during intravenous infusion was investigated in humans. Plasma levels and urinary excretion of NAT, tyrosine, NAC, and total cysteine were determined, and the site of deacetylation was examined by measuring the splanchnic and renal balances. Eleven healthy volunteers were given 5 g of either NAT or NAC as a 4-hour intravenous infusion. Plasma levels of NAT and NAC increased rapidly, accompanied by a 25% increase in tyrosine levels and a 35% decrease in total cysteine. Urinary excretion of NAT and NAC in 4 hours accounted for 56% and 11% of the infused amount, respectively. No net production of tyrosine or cysteine was found from the splanchnic area, but from the kidneys there was a small release of both tyrosine (10 +/- 3 mumol/min) and cysteine (64 +/- 3 mumol/min). We conclude that under these conditions the usefulness of NAT and NAC as precursors for the corresponding amino acids in humans is not apparent.

DrugBank Data that Cites this Article

Drugs