ArticleMolecular and cellular biochemistry2004
Effect of orally administered L-tryptophan on serotonin, melatonin, and the innate immune response in the rat.
Article in Molecular and cellular biochemistry, 2004. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 37 papers.
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Who cites it
37 citing papers in PubMed, 107 citations in OpenAlex.
- Trial
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- Exogenous Melatonin Protects against Oxidative Damage to Membrane Lipids Caused by Some Sodium/Iodide Symporter Inhibitors in the Thyroid.Antioxidants (Basel, Switzerland) · 2023Article
- Reduced Intake of Dietary Tryptophan Improves Beneficial Action of Budesonide in Patients with Lymphocytic Colitis and Mood Disorders.Nutrients · 2023Article
- Melatonin shapes bacterial clearance function of porcine macrophages during enterotoxigenicAnimal nutrition (Zhongguo xu mu shou yi xue hui) · 2022Article
- Nutraceuticals and COVID-19: A mechanistic approach toward attenuating the disease complications.Journal of food biochemistry · 2022Review
- Association between self-reported sleep duration and dietary quality in Mexican school-aged children.Appetite · 2022Article
- Comprehensive effects of various nutrients on sleep.Sleep and biological rhythms · 2022Review
- Tryptophan, Kynurenine and Kynurenic Acid Concentrations in Milk and Serum of Dairy Cows withAnimals : an open access journal from MDPI · 2021Article
- Effects of Duodenal 5-Hydroxytryptophan Perfusion on Melatonin Synthesis in GI Tract of Sheep.Molecules (Basel, Switzerland) · 2021Article
- Neurochemical and Cognitive Beneficial Effects of Moderate Physical Activity and Catechin in Aged Rats.Antioxidants (Basel, Switzerland) · 2021Article
- Nutritional Support of Neurodevelopment and Cognitive Function in Infants and Young Children-An Update and Novel Insights.Nutrients · 2021Review
- The regulation of healthspan and lifespan by dietary amino acids.Translational medicine of aging · 2021Article
- Dietary Tryptophan and the Risk of Metabolic Syndrome: Total Effect and Mediation Effect of Sleep Duration.Nature and science of sleep · 2021Article
- Developmental Programming and Reprogramming of Hypertension and Kidney Disease: Impact of Tryptophan Metabolism.International journal of molecular sciences · 2020Review
- Effect of dietary tryptophan supplementation on growth performance, immune response and anti-oxidant status of broiler chickens from 7 to 21 days.Veterinary medicine and science · 2020Article
- The study of ameliorative effect of dietary supplementation of vitamin C, vitamin E, and tryptophan on Labeo rohita (Cyprinidae) fry exposed to intense light.Fish physiology and biochemistry · 2019Article
- Functions of Macrophages in the Maintenance of Intestinal Homeostasis.Journal of immunology research · 2019Review
Corrections and comments
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Authors and funding
7 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
To assess the effects of external administration of L-tryptophan on the synthesis of serotonin and melatonin as well as on the immune function of Wistar rats, 300 mg of the amino acid were administered through an oral cannula either during daylight (08:00) or at night (20:00) for 5 days. Brain, plasma, and peritoneal macrophage samples were collected 4 h after the administration. The accumulation of 5-hydroxytryptophan (5-HTP) after decarboxylase inhibition was used to measure the rate of tryptophan hydroxylation in vivo. Circulating melatonin levels were determined by radioimmunoassay, and the phagocytic activity of macrophages was measured by counting, under oil-immersion phase-contrast microscopy, the number of particles ingested. The results showed a diurnal increase (p < 0.05) in the brain 5-HTP, serotonin (5-hydroxytryptamine, 5-HT), and 5-hydroxyindolacetic acid (5-HIAA) of the animals which had received tryptophan at 08:00 and were killed 4 h later. In the animals which received tryptophan during the dark period, the 5-HT declined but the 5-HT/5-HIAA ratio remained unchanged. There was also a significant increase (p < 0.05) in nocturnal circulating melatonin levels and in the innate immune response of the peritoneal macrophages in the animals which had received tryptophan at 20:00. The results indicated that the synthesis of serotonin and melatonin, as well as the innate immune response, can be modulated by oral ingestion of tryptophan.
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