Glysinireseptoren

Glycinireseptoren, often abbreviated as GlyRs, are inhibitory ligand-gated ion channels found in the central nervous system of vertebrates. They are primarily located in the spinal cord and brainstem, where they play a crucial role in modulating neuronal excitability. The primary endogenous ligand for GlyRs is the amino acid glycine, though other molecules can also bind and influence their activity.

GlyRs belong to the Cys-loop receptor superfamily, which also includes nicotinic acetylcholine receptors, GABA-A receptors, and 5-HT3 receptors. They are typically pentameric complexes assembled from various subunits, most commonly alpha (α1-4) and beta (β) subunits. The specific combination of these subunits determines the receptor's pharmacological properties and localization. For instance, homomeric receptors composed solely of α1 subunits are found in the adult spinal cord, while heteromeric receptors containing β subunits are more prevalent during development and in other brain regions.

Upon binding of glycine, GlyRs undergo a conformational change that opens an integral ion pore, allowing the passage of chloride ions (Cl-) into the neuron. This influx of negative charge hyperpolarizes the neuronal membrane, making it less likely to fire an action potential. This inhibitory effect is essential for processes such as motor control, sensory processing, and pain modulation. Dysregulation of GlyR function has been implicated in various neurological disorders, including spasticity, epilepsy, and schizophrenia, making them a target for therapeutic intervention.