Glycine is a major neurotransmitter in the mammalian central nervous system. The glycine receptor is a ligand gated Cl- channel, mediating synaptic inhibition in the spinal cord, retina and regions of the brain. The glycine receptor is a pentamer consisting of α and β subunits. To date there are four known α-subunit isoforms (α1- α4) encoded by different genes.In humans, two alternative splice variants of the glycine receptor α3 have been described: α3L, and α3K where the α3L splice variant bears an additional segment of 15 amino acids within the long cytoplasmic TM3-4 loop. These variants differ in their desensitization kinetics.
