Excitatory neurotransmitters are the chemical messengers that encourage neurons to fire and induce an action in the body and brain. Excitatory neurotransmitters are involved in learning and memory, and they also play an important role in the production of glutathione, the “master antioxidant.”
Examples of excitatory neurotransmitters include glutamate, epinephrine, and norepinephrine.
Neurotransmitters: Excitatory And Inhibitory
While excitatory neurotransmitters encourage action, inhibitory neurotransmitters are less likely to make a neuron fire an action. Inhibitory neurotransmitters are calming and relaxing — while excitatory neurotransmitters are stimulating. The main inhibitory neurotransmitter in the brain is called gamma amino butyric acid, or GABA.
In an ideal state, your brain’s excitatory and inhibitory neurotransmitters balance each other out, with neither becoming a dominant force. However, sometimes things can get tipped to one side or the other.
Glutamate Excitotoxicity
The primary excitatory neurotransmitter in the brain is called glutamate. While glutamate is a valuable presence in the brain, it is ideally balanced by GABA.
When there’s too much glutamate in the brain (and not enough GABA), this can create overexcited nerve cells, which in turn can lead to brain cell damage or death. This is known as excitotoxicity.
Furthermore, when GABA levels are low and glutamate rises, it’s believed that conditions like anxiety, depression, insomnia, and neurodegenerative diseases can result.
References
https://www.ncbi.nlm.nih.gov/books/NBK539894/
https://www.ncbi.nlm.nih.gov/books/NBK537267/
http://www.ajnr.org/content/22/10/1813
https://link.springer.com/referenceworkentry/10.1007/978-1-4614-5836-4_125?noAccess=true