A cell-permeable triazolothienopyrimidine compound that acts as a reversible urea transporter B (UT-B)-selective inhibitor (IC50 = 10.3 and 25.1 nM against urea influx using human and mouse erythrocytes, respectively) by targeting a UT-B intracellular site in a urea-competitive manner, exhibiting little effect toward UT-A1, UT-A3, AQP1, CFTR, or TMEM16A channel activities and no cytotoxicity in MDCK cultures (100% viability after 24 h 10 µM inhibitor treatment). Shown to effectively decrease maximum urinary concentration (2.3- and 3.7-fold of basal [urea], respectively, with or without inhibitor; 300 µg/300 µl/mouse i.p.) and increase urination volume (236 vs.109 µl/4h, respectively, with or without inhibitor) from antidiuretic dDAVP- (1 µg/kg; administered 1 h after inhibitor) treated wild-type, but not UT-B^-/-, mice in vivo. Despite its short half-life (t_1/2 = 2.8 min) in in vitro rat hepatic microsomes stability tests, an average inhibitor concentration of 390 µM in blood can be reached in mice even 6 h after a single i.p. dose of 200 µl per animal.

Cell permeable: yes

Primary Target
urea transporter B

Reversible: yes

Packaged under inert gas

Anderson, M.O., et al. 2012. J. Med. Chem.55, 5942.
Yao, C., et al. 2012. J. Am. Soc. Nephrol.23, 1210.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Toxicity: Standard Handling (A)