(S)-SNAP 5114 is a selective inhibitor of GABA transport with IC50 values of 5, 21 and 388 μM for hGAT-3, rGAT-2 and hGAT-1, respectively [1].

γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system (CNS) and plays a critical role in Huntington’s disease, Parkinson’s disease, epilepsy, schizophrenia and Alzheimer’s disease. GABA transporters transport GABA from extra- to intracellular side of glial and neuronal cells [2].

(S)-SNAP 5114 is a selective GABA transport inhibitor. In HEK-293 cell lines expressing mGAT1-4, (S)-SNAP 5114 exhibited inhibitory potencies with pIC50 values of 4.07, 5.29 and 5.71 for mGAT1, mGAT3 and mGAT4 respectively and inhibited mGAT2 by 56% [2]. SNAP-5114 (100 μM) increased GABA levels to 247% in the thalamus. In juvenile rats with maximal electroshock, SNAP-5114 inhibited tonic hindlimb extension. In DBA/2 mice, SNAP-5114 inhibited sound induced convulsions in a dose-dependent way with ED50 value of 110 μmol/kg [3]. In rats, SNAP5114 (10, 50, 100 or 200 μg) inhibited the late-phase response in the formalin test and prolonged withdrawal latencies in the tail flick test, which suggested that SNAP5114 inhibited chemical and thermal nociception. In the chronic constriction injury rats, SNAP5114 inhibited mechanical allodynia in a dose-dependent way [4].

References:
[1].  Borden LA, Dhar TG, Smith KE, et al. Cloning of the human homologue of the GABA transporter GAT-3 and identification of a novel inhibitor with selectivity for this site. Receptors Channels, 1994, 2(3): 207-213.
[2].  Pabel J, Faust M, Prehn C, et al. Development of an (S)-1-{2-[tris(4-methoxyphenyl)methoxy]ethyl}piperidine-3-carboxylic acid [(S)-SNAP-5114] carba analogue inhibitor for murine γ-aminobutyric acid transporter type 4. ChemMedChem, 2012, 7(7): 1245-1255.
[3].  Dalby NO. GABA-level increasing and anticonvulsant effects of three different GABA uptake inhibitors. Neuropharmacology, 2000, 39(12): 2399-2407.
[4].  Kataoka K, Hara K, Haranishi Y, et al. The antinociceptive effect of SNAP5114, a gamma-aminobutyric acid transporter-3 inhibitor, in rat experimental pain models. Anesth Analg, 2013, 116(5): 1162-1169.