| Background: | GABA(B) receptor 1, a GABA(B) Receptor, forms a heterodimer with GABA(B) receptor 2 to mediate the effects of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in the central nervous system. Activation of this receptor leads to fast synaptic inhibition. Reduced GABA(B) receptor 1a-b expression is implicated in the pathophysiology of temporal-lobe epilepsy. In primates, GABA(B) receptors are widely distributed and are located to subserve both pre- and postsynaptic roles in controlling synaptic transmission in the primate basal ganglia. Five alternatively spliced protein isoforms of GABA(B) receptor 1 have been identified. GABA(B) receptor 1 is widely expressed, with highest levels reported in brain, and lower levels in gastrointestinal tract, kidney, and uterus. ESTs have been isolated from a wide variety of tissues, including adrenal, brain, breast, colon, embryo, eye, ganglion, head/neck, heart, heart/melanocyte/uterus, liver/spleen, lung, nerve, placenta, prostate, stomach, testis, and tonsil libraries, among others. |