What is a gabaergic neuron and how is it used?

1 Answer
Nov 14, 2017

It's not the Neuron that is GABA-ergic, it's the receptor...

Explanation:

Neurons can communicate with each other via electrical signals (via electrical synapses), but most of it is done in a (bio)chemical way: via the (chemical) synapse . It is a one-way signal though, at least at the synapse level, as the Pre-Synaptic Neuron (Pre-SN) acts as a transmitter, the Post-Synaptic Neuron as receiver.

Note : a Post-S Neuron can loop back to the Pre-SN in a neural network and thus give "feedback", but that's another synapse...

The signal is carried over via the Neurotransmitter of choice, which is released by the Pre-SN into the cleft between the neurons (the Synapse ).
The Post-SN has receptors which are sensitive to the released Neurotransmitter, and in its presence will be triggered accordingly.

Any given Neuron will have an electrical charge inside called the Resting Potential. This usually is between -40mV and -60mV: it can vary.

If a receptor is activated then the neuron will react by changing the concentrations of #Na^+#, #K^+# , #Cl^-# and #Ca^"2+"# -ions.

I'm not going into details here, for more info read this:
neuroscience.uth.tmc.edu/s1/introduction.html.

In most cases, the effect of the neurotransmitter (more then 90 have been identified at the time of writing it seems) will be Excitatory: it will depolarise the cell. If the cell is depolarised beyond a certain threshold, it will result in an Action Potential: a spike in potential, and the neuron "fires".

Whether or not a neuron will reach Action Potential is dependent on the Summation of all signals it receives at any given time: their strength, frequency and number:
enter image source here
Picture: Courtesy of University of Texas, mcGovern Medical School.

There are some Neurotransmitters though, that have the opposite effect: they are Inhibitory. Their effect is HyperPolarisation of the cell, thereby negating the effect of the Excitatory transmitters.

GABA (Gamma-Amino-Butyric Acid) is one of the, if not the main ,inhibitory transmitter. There are others, like apparently Serotonin, though in a lot of sources that is reported as having an Excitatory effect as well. To make things even more confusing, in some instances GABA itself can have an Excitatory effect. That discussion is outside the scope of this question, however.....

So, in short: GABA calms a neuron down...