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Medical and Ecological Considerations of L-Dopa and 5-HTP in Seeds


IT is well known that 5-hydroxy-L-tryptophan (5-HTP) occurs in low concentration in mammalian brain serving as the precursor of 5-hydroxytryptamine (5-HT, serotonin). Furthermore, 5-HTP but not 5-HT can pass readily across the blood-brain barrier so that the physiological effects associated with an increase of 5-HT in the brain may be induced in rats and dogs by the interperitoneal injection of 5-HTP1,2. A recent report indicated that 5-HTP produced improvement in a patient suffering from the Parkinson-like symptoms of chronic manganese poisoning after treatment with L-3,4-dihydroxy-phenylalanine (L-dopa) had aggravated his condition3.

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BELL, E., JANZEN, D. Medical and Ecological Considerations of L-Dopa and 5-HTP in Seeds. Nature 229, 136–137 (1971).

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