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Glutamate as a possible precursor for GABA in the brain?

Charles Bronson

Bluelighter
Joined
Sep 9, 2011
Messages
193
Location
South East Queensland, Australia.
Synthesis

GABA does not penetrate the blood-brain barrier; it is synthesized in the brain. It is synthesized from glutamate using the enzyme L-glutamic acid decarboxylase and pyridoxal phosphate (which is the active form of vitamin B6) as a cofactor via a metabolic pathway called the GABA shunt. This process converts glutamate, the principal excitatory neurotransmitter, into the principal inhibitory neurotransmitter (GABA).[33][34]

From Wikipedia,

Could glutamate restore/vitamin B5, GABA, in individuals depleted of GABA through years of benzodiazepine use?
 
In my experience, GABA does cross the blood brain barrier given a sufficient dose (a heaping teaspoon always sends me into an awesome and refreshing sleep at the end of the day). It's possible that this is a placebo in that the peripheral effects of tingling in the extremities and what-not remind me of calm states of mind but whatever, it works for me. L-Glutamine also seem to have an anxiolytic effect. L-Theanine is a known anxiety reducing amino acid.
 
You may find picamilon interesting:

http://en.wikipedia.org/wiki/Picamilon

Picamilon is able to cross the blood-brain barrier[5] and then is hydrolyzed into GABA and niacin. The released GABA in theory would activate GABA receptors potentially producing an anxiolytic response.[6] The second released component, niacin acts as a strong vasodilator,[7] which might be useful for the treatment of migraine headaches.[8][9]
 
Because glutamate is the primary excititory neurotransmitter, raising levels of intracerebral glutamate with the goal of increasing levels of gaba is counterproductive. Also, there are likely other bottlenecks to increased intersynaptic gaba than available precursor.

ebola
 
Because glutamate is the primary excititory neurotransmitter, raising levels of intracerebral glutamate with the goal of increasing levels of gaba is counterproductive. Also, there are likely other bottlenecks to increased intersynaptic gaba than available precursor.

ebola

Considering that the brain's homeostastic mechanisms are not being tampered with, it seems, to me, that this should not be a concern since the body will be tending towards balance, no matter how many and which raw materials are available. Is there a flaw in this reasoning?
 
Yes. Insofar as one attempts to affect the brain, one attempts to supersede homeostatic mechanisms. If the brain "always tends toward balance", why intervene in the first place?
...
In my experience, GABA does cross the blood brain barrier given a sufficient dose

You cannot confirm this via personal experience.

ebola
 
I'm pretty sure that if you eat any amount of protien (esp. tasty "umami" flavours such as meat broth, cheese, MSG in chinese food etc) you get enough dietary glutamate anyway. Don't forget glutamate is an amino acid!

I'm also pretty sre long term BZD usage does not deplete GABA, it merely reduces how efficacious it is at triggering GABAergics.

As ebola pointed out, there is also the small matter of fucking around with the Glutamate Transporter protien to actually raise intracerebral Glu cocnentrations (not a smart idea).
 
So will taking a vitamin B complex with those GABA capsules help with the process of it creating some GABA neurotransmitters in the brain? Wtf is the point of these $20 bottles of GABA at GNC stores if everyone says it doesn't cross the BBB, shouldn't taking the GABA amino acid capsule some how help produce more GABA production in your brain by not directly crossing the BBB? Sorry if i sound confusing, i feel kind of fried right now. Is there some other type of nervous system where this GABA would be useful, without targeting the brain still giving a calming state to the body? If not ... fucking scammers with these GABA supplements.
 
So will taking a vitamin B complex with those GABA capsules help with the process of it creating some GABA neurotransmitters in the brain?

No. GABA does not cross the BBB.

Wtf is the point of these $20 bottles of GABA at GNC stores if everyone says it doesn't cross the BBB

They have no point.

ebola
 
Straying a bit off from the initial topic of the thread, but isn’t it possible that oral GABA is causing some effect centrally without crossing the blood brain barrier? (I know, seems impossible at first, but bear with me)

Couldn’t the huge concentrations of systemic GABA saturate the enzyme responsible for GABA metabolism, and therefore prevent GABA in the brain from breaking down?

Or the high levels of systemic GABA could create a large concentration gradient preventing any of the centrally located GABA from crossing into the periphery?
 
Couldn’t the huge concentrations of systemic GABA saturate the enzyme responsible for GABA metabolism, and therefore prevent GABA in the brain from breaking down?

No, as it wouldn't saturate the portion of the enzyme present in the brain.

Or the high levels of systemic GABA could create a large concentration gradient preventing any of the centrally located GABA from crossing into the periphery?

No, as the BBB barrier already prevents diffusion of GABA into the periphery.

ebola
 
I'm pretty sure that if you eat any amount of protien (esp. tasty "umami" flavours such as meat broth, cheese, MSG in chinese food etc) you get enough dietary glutamate anyway. Don't forget glutamate is an amino acid!

..and thankfully the blood brain barrier protects us otherwise we would literally have dead brain tissue. It like anything is not invisible, hence the concern about MSG (for example when in hypoglycaemic states or those sensitive may display minor leakiness, still if there was any kind of serious influx it would most definitely result in neuronal cell death). A good reason NOT to mess glutamate (particularly in order to increase GABA).

Considering that the brain's homeostastic mechanisms are not being tampered with, it seems, to me, that this should not be a concern since the body will be tending towards balance, no matter how many and which raw materials are available. Is there a flaw in this reasoning?

That's like saying give someone glucose to produce hypoglycaemia.
 
Benzodiazepines work by increasing the efficiency of a natural brain chemical, GABA, to decrease the excitability of neurons. This reduces the communication between neurons and, therefore, has a calming effect on many of the functions of the brain.

GABA controls the excitability of neurons by binding to the GABAA receptor.

Now, through years of use of benzodiazepines, you can restore the GABA back to the same level, if not even more than you normally had, by taking a couple of simple, OTC amino acids:
L-Glutamine
Vitamin B MEGA Complex

L-Glutamine converts to L-Glutamate which, when combined with PLP (Vitamin B6 complex), converts over to GABA.

(PLP plays a role in the conversion of dopa into dopamine, allows the conversion of the excitatory neurotransmitter glutamate to the inhibitory neurotransmitter GABA.)

Be careful though, as some people who are sensitive or taking other medications, should consult their doctors, due to risk of neurotoxicity. This is incorrect.
1. Long-term benzodiazapine use causes downregulation of GABA-a receptors, not depletion of intersynaptic GABA.

Dick head, what do you think is released when neurons are too excited? GABA. Benzodiazepines work by increasing the efficiency of GABA to calm down these excited neurons. Astrocytes express plasma membrane transporters such as glutamate transporters for several neurotransmitters, including glutamate, ATP, and GABA. More recently, astrocytes were shown to release glutamate or ATP in a vesicular, Ca2+-dependent manner.

Glutamate decarboxylase or glutamic acid decarboxylase (GAD) is an enzyme that catalyzes the decarboxylation of glutamate to GABA and CO2. GAD uses PLP as a cofactor.

In mammals, GAD exists in two isoforms encoded by two different genes - GAD1 and GAD2. These isoforms are GAD67 and GAD65 with molecular weights of 67 and 65 kDa, respectively.GAD1 and GAD2 are expressed in the brain where GABA is used as a neurotransmitter, GAD2 is also expressed in the pancreas.

Glutamate also serves as the precursor for the synthesis of the inhibitory GABA in GABA-ergic neurons. This reaction is catalyzed by glutamate decarboxylase (GAD), which is most abundant in the cerebellum and pancreas. Inhibitory GABA is released when benzodiazepines are taken. Once bound to the benzodiazepine receptor, the benzodiazepine ligand locks the benzodiazepine receptor into a conformation in which it has a greater affinity for the GABA neurotransmitter. This increases the frequency of the opening of the associated chloride ion channel and hyperpolarizes the membrane of the associated neuron. The inhibitory effect of the available GABA is potentiated, leading to sedatory and anxiolytic effects.

Acamprosate (calcium homotaurinate) is believed to block glutaminergicN-methyl-Daspartate receptors and activate 3-aminobutyric acid (GABA) type A receptors.

Oh yeah and also, Pregabalin increases neuronal GABA levels by producing a dose-dependent increase in glutamic acid decarboxylase activity.



2. Neither GABA nor glutamate pass the BBB, so the proposed methods wont increase the quantity of GABA synthesized.

Who the fuck said anything about GABA? GABA is a bunch of bullshit, like downregulation and upregulation, there's no scientific evidence to support these claims, so don't mention GABA again on my thread please.

L-glutamine does indeed bass the blood brain barrier. Because it converts itself to glutamic acid (glutamate) and with the aid of PLP, converts into GABA.

Myself Consequently, the
major (and direct) trigger for local glucose utilization would
remain glutamate. Consistent with this view is the fact that most
GABAergic neurons are locally acting interneurons activated by
glutamatergic inputs (34). Thus glutamate, by activating GABA
neurons, could lead to an overall inhibitory activity in a given
cortical area; yet glutamate release and uptake by astrocytes
would stimulate glycolysis in astrocytes and constitute a sufficient
signal coding for increased activity of GABAergic neurons
as well. It would therefore appear that the most relevant, and
possibly sufficient signal, linking neuronal activity (both excitatory
and inhibitory) with metabolism is glutamate, which would
mediate the appropriate metabolic coupling both for excitatory
and inhibitory neurons.


Sources:
Glutamine - http://www.socialanxietysupport.com/...lements-30805/
 
fixed title. You guys might want to look into upregulating the GABA biosynthetic pathway heads up.
 
From my experience, my prescribed medications work more effectively if I have been taking a multi vitamin. IMHO, I believe if the body has the right balance of nuitrients, both GABA related presciriptions and the stimulating neurotransmitters scripts (Norephedrine) take more noticable effects. I don't mean night and day difference but mild yet noticable effects. For example, zinc is suppose to help out the ADD medications. It seems more effective if I take a multi vitamin which includes zinc before taking my medication. These vitamins and minerals seem to help in two ways. #1 they assist with the actual "channels" (example calcium channel) and #2 they help provide the building blocks needed to create the nuero transmitters themselves.

Just my views :)
 
No. GABA does not cross the BBB.



They have no point.

ebola


ebola, ive also read GABA does not cross BBB but many people who have taken it do comment on being more relaxed. im confused if it can all be placebo. ive experienced it, but you dont give a shit about personal experience type of arguments, so how about telling me if it doesnt work at all, how come it still sells for all those years and people i talked to, or reviews i read claim it does work in combinations or different ways of taking it like sublingual ?
 
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