I have read that GABA is an inhibitory neurotransmitter, but I still don’t comprehend how they can prevent anxiety or treat a panic attack.
Is panic disorder due to overactivation of certain neurons and brain areas? If so, which ones? Do drugs that increase GABA like benzos just cause them to return to a more baseline level?
Is it a serotonin or norepinephrine or dopamine reuptake inhibitor?
Low levels of serotonin and norepinephrine both have an impact anxiety and irritability. All 3 impact mood.
Reuptake inhibitors work by making neurotransmitters stick around longer to be absorbed by the receptors instead of being quickly taken up from whence they were released.
It seems that the body reacts to this increase in the availability of those neurotransmitters by upregulating the number of receptors.
In other words, it’s like giving your sero/norepi/dop receptors a workout so they increase in capability. Which is why reuptake inhibitors take several weeks to show benefits.
You mention GABA medications. I’ve read that GABA supplements don’t cross the blood brain barrier so they may not be much use.
Unless you weren’t talking about serotonin or norepinephrine or dopamine reuptake inhibitors in which case this whole post is irrelevant.
By GABA medications I mean benzodiazepines and barbiturates. Both classes work on GABA and both decrease anxiety.
Think of it more as “we know that signals using this neurotransmitter are sent when someone is panicking”. “let’s block it, and they might calm down”. (I don’t think the actual drug discovery was done with knowledge of what neurotransmitters they were targeting, they just found that people calmed down when certain substances were given)
*Why *those signals are being sent could be countless reasons. The medication is aimed at the symptoms. Among other problems, lots of other brain pathways happen to use this neurotransmitter. That’s why there are a crapton of side effects when these drugs are given. You’re inhibiting signals meant for other things.
No. GABA agonists affect GABA, which is a completely different neurotransmitter (short for gamma-Aminobutyric acid). Some are mostly excitatory (glutamate), some like GABA are mostly inhibitory, most have differing effects in different parts of the nervous system. I do not believe that most benzos affect reuptake at all, but there are many, many other ways to affect the functioning of a synapse.
The baseline level is the left at which they normally perform at, there is no “normal” level.
Some drugs don’t cross the blood-brain barrier, but they can still increase that NT by e.g. increasing the levels of a precursor chemical that is then synthesized into the NT (I don’t think that is the case in most GABA agonists, but for other drugs).
Inhibition decreases excitation. Anxiolytic drugs work more strongly in brain regions implicated in anxiety, while not affecting GABA as much in other regions. E.g. GABA[sub]A[/sub] receptors, but not GABA[sub]B[/sub]. Some brain regions implicated (not a complete list) are the amygdala and hippocampus.
And benzos have overcome barbiturates for the most part because they are safer (but still highly addictive) due to not affecting other brain regions as much and being more tolerant of overdose.
My understanding is the drugs in question (benzos and barbituates) attach to chloride ion channels, causing hyperpolarization of a neuron and increasing the firing threshold by (I think) making the neurons more negatively charged. Benzos cause the channel to open more, while barbituates cause the channel to stay open longer, I think that is why benzos are harder to OD on (for whatever reason, the ion channel opening more does less damage than it staying open longer).
Either way, I guess I still don’t understand how this relates to anxiety. Does anxiety originate in the limbic system (amygdala, etc)? Is fight or flight a hyper reaction of neurons (neurons firing far too often)? On anxiolytics many people can still function but it cuts their anxiety. Naturally if you take too much you end up confused, fatigued, etc but many people can still function (drive, communicate, stay awake, think, etc) while their anxiety decreases on GABA drugs.
Does anxiety disorder or a panic attack lower the firing threshold in neurons?