Background:

SKF89976A hydrochloride is a selective GABA transporter (GAT-1) inhibitor with IC50s of 0.28 μM, 137.34 μM and 202.8 μM for GAT-1, GAT-2 and GAT-3 in CHO cells, respectively.

SKF89976A has a weak antiallodynic action. SKF89976A weakly inhibits serotonin transporter (SERT), noradrenaline transporter (NET), and dopamine transporter (DAT) in chinese hamster ovary (CHO) cells stably expressing each transporter using a substrate uptake assay, with IC50 values of 3514 , 202.13, and 728.8, respectively[1]. SKF89976A is a GABA-transport blocker. GABA (1 mM) elicited an inward current that is completely suppressed by the GABA transport inhibitors tiagabine (10 μM) and SKF89976A (100 μM), but is unaffected by 100 μM picrotoxin. 100 μM SKF 89976-A is known to block the transport of GABA into cells, completely eliminated the GABA-elicited current in a reversible fashion[2]. SKF89976A is a nontransportable blockers of GAT-1. SKF89976-A also suppresses baseline inward currents that likely result from tonic GAT activation by background GABA. SKF89976A (100 μM) reversibly reduces GAT currents in every studied cell by 67.9±4.4% (n=19). Intracellular perfusion of 20 μM SKF89976-A progressively reduced and blocked GABA-induced GAT currents without blocking GABAAR-mediated currents (n=4)[3].

SKF89976A produces a weak antiallodynic response when administered i.v. (0.3 mg/kg). The i.t. injection of SKF89976A dose-dependently ameliorates the reduction in the withdrawal threshold in PSL model mice[1].

参考文献:
[1]. Jinzenji A, et al. Antiallodynic action of 1-(3-(9H-Carbazol-9-yl)-1-propyl)-4-(2-methyoxyphenyl)-4-piperidinol (NNC05-2090), a betaine/GABA transporter inhibitor. J Pharmacol Sci. 2014;125(2):217-26.
[2]. Kreitzer MA, et al. Glutamate modulation of GABA transport in retinal horizontal cells of the skate. J Physiol. 2003 Feb 1;546(Pt 3):717-31.
[3]. Barakat L, et al. GAT-1 and reversible GABA transport in Bergmann glia in slices. J Neurophysiol. 2002 Sep;88(3):1407-19.