Posted by Larry Hoover on December 15, 2003, at 6:14:10
In reply to Re: Motivation problems and alternative meds » btnd, posted by Ron Hill on December 10, 2003, at 20:54:33
> Another approach that might be worthy of consideration is to take tyrosine together with tryptophan. I blocked, copied, and pasted the following quote from this article: http://www.smartnutrition.info/JamesSouth-tryptophan.htm
>
> <start quote>
> Van Praag’s research has shown that for many people suffering depression, combining the amino-acid tyrosine with tryptophan works much better than taking tryptophan alone. These would be Young’s "apathetic inhibited" types, where both the serotonin tranquillity/ well being circuits and the "get up and go" vigorous action dopamine/ noradrenaline circuits are underactive.
> <end quote>
>
> -- RonRon, it isn't clear from this post if you're considering adding in some tryptophan, but theanine inhibits serotonin synthesis, so it may counterproductive for you. In contrast, theanine directly stimulates dopamine release.
Lar
Biosci Biotechnol Biochem. 1998 Apr;62(4):816-7.Theanine-induced reduction of brain serotonin concentration in rats.
Yokogoshi H, Mochizuki M, Saitoh K.
Laboratory of Nutritional Biochemistry, School of Food and Nutritional Sciences, University of Shizuoka, Japan. yokogosi@fnsl.u-shizuoka-ken.ac.jp
Following the administration of theanine, the brain tryptophan content significantly increased or tended to increase, but the contents of serotonin and 5-hydroxyindole acetic acid (5HIAA) decreased. The use of inhibitors of serotonin metabolism enable us to speculate that theanine reduced serotonin synthesis and also increased serotonin degradation in the brain.
Neurochem Res. 1998 May;23(5):667-73.Effect of theanine, r-glutamylethylamide, on brain monoamines and striatal dopamine release in conscious rats.
Yokogoshi H, Kobayashi M, Mochizuki M, Terashima T.
School of Food and Nutritional Sciences, The University of Shizuoka, Yada, Shizuoka, Japan. yokogosi@fns1.u-shizuoka-ken.ac.jp
Theanine, r-glutamylethylamide, is one of the major components of amino acids in Japanese green tea. Effect of theanine on brain amino acids and monoamines, and the striatal release of dopamine (DA) was investigated. Determination of amino acids in the brain after the intragastric administration of theanine showed that theanine was incorporated into brain through blood-brain barrier via leucine-preferring transport system. The concentrations of norepinephrine, 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindole acetic acid (5HIAA) in the brain regions were unaffected by the theanine administration except in striatum. Theanine administration caused significant increases in serotonin and/or DA concentrations in the brain, especially in striatum, hypothalamus and hippocampus. Direct administration of theanine into brain striatum by microinjection caused a significant increase of DA release in a dose-dependent manner. Microdialysis of brain with calcium-free Ringer buffer attenuated the theanine-induced DA release. Pretreatment with the Ringer buffer containing an antagonist of non-NMDA (N-methyl-D-aspartate) glutamate receptor, MK-801, for 1 hr did not change the significant increase of DA release induced by theanine. However, in the case of pretreatment with AP-5, (+/-)-2-amino-5-phosphonopentanoic acid; antagonist of NMDA glutamate receptor, the theanine-induced DA release from striatum was significantly inhibited. These results suggest that theanine might affect the metabolism and/or the release of some neurotransmitters in the brain, such as DA.
poster:Larry Hoover
thread:288550
URL: http://www.dr-bob.org/babble/alter/20031204/msgs/289930.html