Posted by PeterJ on April 28, 2000, at 2:52:00
In reply to Re: More Qs for PeterJ - Butting in., posted by Scott L. Schofield on April 27, 2000, at 7:57:46
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> To give tyrosine a good shot at doing anything in the brain, it needs to get there in the first place.I agree. Tyrosine or phenylalanine must be taken without protein. It may be even better to take it on a completely empty stomach as the insulin release caused by food may lead to the amino acids being taken up by muscle instead of brain.
Saturation of tryosine hyroxylase is indeed rate-limiting. The enzyme is normally saturated but may not be in conditions of high dopamine turnover.
Another point to consider is that some of the actions of tyrosine or phenylalanine may be due to peripheral conversion to adrenaline or noradrenaline, either in the adrenals or in sympathetic neurons. Having taken tyrosine, phenylalanine (d- and/or l-) and l-dopa, I find that tyrosine and l-phenylalanine produced more pronounced peripheral effects (e.g. tachychardia) and a more adrenergic rather than dopaminergic feeling.
Peter
poster:PeterJ
thread:30864
URL: http://www.dr-bob.org/babble/20000420/msgs/31548.html