SB271046 Hydrochloride is a potent, selective and orally active 5-HT6 receptor antagonist with pKi of 8.9.IC50 Value: 8.9(pKi)Target: 5-HT6 Receptorin vitro: SB 271046 hydrochloride is a sulfonamidal benzothiophene derivative that has been shown to act as a selective 5-HT6 antagonist with pKi values of 9.02-8.92, 6.55, 6.35, 6.27, 6.05, 5.95, 5.76, 5.73, 5.62, 5.55, 5.41, 5.39, 5.27 and 200-fold selective over 55 other receptors, enzymes and ion channels.in vivo: SB-271046 is moderately brain penetrant (10%), subject to low blood clearance (7.7 mL/min/kg) with a good half-life in rats (4.8 hours), and has excellent oral bioavailability (>80%). SB-271046 produces 3-fold and 2-fold increases in extracellular glutamate levels in both frontal cortex and dorsal hippocampus of rats, respectively, which may be used for the treatment of cognitive and memory dysfunction. SB-271046 (20 mg/kg, orally gavage) 30 min prior to training Wistar rats, is found to reverse significantly the amnesia produced by administering scopolamine (0.8 mg/kg, i.p.) in the 6 hours post-training period. SB-271046 progressively and significantly decreases platform swim angle and escape latencies over the five sequential trials on four consecutive daily sessions compared to vehicle-treated controls in aged rats. SB-271046 also improves task recall as measured by significant increases in the searching of the target quadrant on post-training days 1 and 3. SB-271046 (10 mg/kg, s.c.) produces a significant, tetrodotoxin-dependent, increase in extracellular levels of both glutamate and aspartate within the frontal cortex of rats, reaching maximum values of 375.4% and 215.3% of preinjection values, respectively.
[1]. Routledge C, et al. Characterization of SB-271046: a potent, selective and orally active 5-HT(6) receptor antagonist. Br J Pharmacol. 2000 Aug;130(7):1606-12. [2]. Bromidge SM, et al. 5-Chloro-N-(4-methoxy-3-piperazin-1-yl- phenyl)-3-methyl-2-benzothiophenesulfon- amide (SB-271046): a potent, selective, and orally bioavailable 5-HT6 receptor antagonist. J Med Chem. 1999 Jan 28;42(2):202-5. [3]. Dawson LA, et al. The 5-HT(6) receptor antagonist SB-271046 selectively enhances excitatory neurotransmission in the rat frontal cortex and hippocampus. Neuropsychopharmacology. 2001 Nov;25(5):662-8.