Dose-response decrease in plasma tryptophan and in brain tryptophan and serotonin after tryptophan-free amino acid mixtures in rats.

E A Moja; P Cipolla; D Castoldi; O Tofanetti

doi:10.1016/0024-3205(89)90497-9

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Dose-response decrease in plasma tryptophan and in brain tryptophan and serotonin after tryptophan-free amino acid mixtures in rats.

E A Moja·P Cipolla·D Castoldi·O Tofanetti

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Abstract

Rats fasted 15 hours were treated p.o. with increasing amounts (660 and 1320 mg/kg body weight) of a mixture containing a fixed proportion of seven essential amino acids (L-phenylalanine 13.6%, L-leucine 6.0%, L-isoleucine 12.1%, L-methionine 12.1%, L-lysine 30.3%, L-threonine 10.6%, L-valine 15.2%) and lacking tryptophan. The mixtures produced a dose-response decrease of free (by 34% after the lower dose and by 58% after the higher dose of the mixture) and total (by 10 and 31%) plasma tryptophan and of brain tryptophan (by 38 and 65%), serotonin (by 17 and 41%) and 5-hydroxyindole acetic acid (by 21 and 49%). The mechanisms of these changes are discussed.

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Amino Acids Animals Brain Hydroxyindoleacetic Acid Male Rats Rats, Inbred Strains Serotonin Tryptophan Journal Article

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E A Moja, P Cipolla, D Castoldi, O Tofanetti. 1989. Dose-response decrease in plasma tryptophan and in brain tryptophan and serotonin after tryptophan-free amino acid mixtures in rats.. https://doi.org/10.1016/0024-3205(89)90497-9

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