GABAAreseptori

GABAAreseptori, also known as GABA-A receptors, are ligand-gated ion channels that play a crucial role in the central nervous system of vertebrates. They are the principal mediators of inhibitory neurotransmission, primarily by responding to the neurotransmitter gamma-aminobutyric acid (GABA). When GABA binds to its receptor, it causes the channel to open, allowing chloride ions to flow into the neuron. This influx of negative charge hyperpolarizes the neuron, making it less likely to fire an action potential.

These receptors are pentameric structures, meaning they are composed of five protein subunits arranged around a central ion-permeable pore. There are numerous subunit types, including alpha, beta, gamma, delta, epsilon, pi, and theta, with several subtypes within each. The specific combination of subunits determines the receptor's pharmacological and physiological properties, such as its affinity for GABA, its ion channel conductance, and its response to various drugs.

GABAA receptors are widely distributed throughout the brain and spinal cord. They are found on both excitatory and inhibitory neurons, and their modulation has significant implications for a variety of neurological and psychiatric conditions. For instance, drugs that enhance GABAA receptor function, such as benzodiazepines and barbiturates, are used to treat anxiety, insomnia, and epilepsy. Conversely, substances that block GABAA receptors, like bicuculline, can induce seizures. The complexity of GABAA receptor subunit composition and their intricate roles make them a significant target for therapeutic intervention.