Our bodies are composed of four basic tissue types: epithelial, muscular, connective, and nervous. Within nervous tissue, a dense web of 100 billion neurons (the functional unit of the nervous system) are constantly intercommunicating. This communication takes the form of both electrical and chemical signals. Perhaps the most simplified signaling essentially involves an on/off switch. In the nervous system, this takes the form of excitatory or inhibitory signals that alter the charge separation across a neuron’s membrane.
The membrane of a neuron typically has a charge separation of around -70 millivolts. That is to say, the interior of a resting cell contains negatively charged ions equaling around -70 millivolts. When communicating excitatory signals, we primarily use the amino acid glutamate. Inhibitory signals are typically communicated using gamma aminobutyric acid (GABA).
Signaling molecules, such as GABA, can deliver their message by interacting with their receptor. As one may expect, GABA binds to GABA receptors, of which two main complexes have been detailed: GABAA and GABAB. GABAA receptors act as ion channels, whereas GABAB is coupled to a G protein that catalyses enzymatic reactions within the