Posted by andys on July 29, 2003, at 13:33:16
There's a lot of confusion about tyrosine and phenylalanine (and its benefit, used with dexedrine). I have whittled it down to what makes sense to me, and would like this critiqued by those in the know:
A---It’s the HYDROXYLAZE version of the aminos that cross the blood/brain barrier.B---Tyrosine hydroxylaze is desirable, because it supports brain dopamine and norepinepherine.
Phenylalanine hydroxylaze is NOT desirable, because it gives a stimulant effect in the brain, and in the rebound, may actually DEPLETE brain dopamine and norepinepherine.C---Tyrosine hydroxylaze is converted to L-dopa in the brain, and then converted to dopamine, and to a lesser extent, norepinepherine.
D---The tyrosine hydroxylaze BOTTLENECK:
Although tyrosine hydroxylaze is very desirable in the brain, there is a bottleneck at the blood/brain barrier, where only a minimal amount of tyrosine hydroxylaze can cross into the brain.
Because of this bottleneck, there are only two reasons to take tyrosine:
1---You’re not getting sufficient tyrosine in your diet (which is rarely the case, unless vegetarian).
2---You’re on a stimulant, such as Dexedrine, and tyrosine can restore the dopamine/norepinepherine lost through
Dexedrine use.Where does PEA fit in this equation?
Tyrosine is very beneficial, if taking Dexedrine
Although several articles and actual studies support this, it doesn’t quite make sense: Since the tyrosine hydroxylaze is limited in its amount that can cross the blood/brain barrier, I doubt if MORE is allowed past the barrier, just because dopamine is depleted by Dexedrine.Take tyrosine with juice, on an empty stomach, and not with other protein, aminos, or phenylalanine.
My understanding of this theory is that you can maximize the amount of tyrosine hydroxylaze that crosses the blood/brain barrier, if it isn’t competing with other aminos crossing the barrier at the same time. This is true for other aminos, but especially for phenylalanine, which is why you shouldn’t take phenylalanine within HOURS of taking tyrosine.The reasons to not take phenylalanine
A---The reason for not taking phenylalanine with tyrosine:
Since phenylalanine DIRECTLY converts to phenylalanine hydroxylase, it FLOODS the access to the blood/brain barrier, competing with the tyrosine hydroxylaze. But since phenylalanine DIRECTLY converts into phenylalanine hydroxylaze, it is going to reach the blood/brain barrier faster than tyrosine, which hs several metabolic steps for tyrosine hydroxylaze.B---The reason for not taking phenylalanine AT ALL
1---Phenylalanine gives a short stimulant effect in the brain, but then has a rebound effect of DEPLETING dopamine and norepinepherine.
2---Poop-out of phenylalanine is very common, and, like other stimulants, you have to take some days off, to get the benefit back. However, this yo-yo effect is probably destabilizing for bipolars (or unipolars as well).
poster:andys
thread:246486
URL: http://www.dr-bob.org/babble/20030728/msgs/246486.html