GW3965 hydrochloride (GW3965 HCl) is an effective and specific LXR agonist for hLXRα/β (EC50: 190/30 nM).

LXRα (human):190 nM (EC50), LXRβ (human):30 nM (EC50)

Steady-state drug accumulation assay: AuxB1 and CHrB30 cells are grown to confluency in 12-well (24 mm) tissue culture dishes and the steady-state accumulation of [3H]-vinblastine is measured. Accumulation is initiated by the addition of 0.1 μ Ci [3H]-vinblastine and unlabelled vinblastine to a final concentration of 100 nM . The accumulation of [3H]-paclitaxel is measured using 0.1 μ Ci [3H]-paclitaxel and unlabelled drug to a final concentration of 1 μM . Cells are incubated in a reaction volume of 1 mL for 60 min at 37 ℃ under 5% CO2 in order to reach steady-state. The effect of the modulators XR9576 on [3H]-ligand accumulation is investigated in the concentration range 10-9 - 10-6 M. Modulators are added from a DMSO stock giving a final solvent concentration of 0.2 % (v/v). Following cell harvesting, accumulated drug is measured by liquid scintillation counting and normalized for cell protein content. Plots of amount accumulated as a function of modulator concentration are fitted with the general dose-response equation: Y={(a-b)/(1+(X/c)d)}+b Where: Y=response; a=initial response; b=final response; c=EC50 concentration; d=slope value; X=drug concentration.

Cells are seeded in 96 wells and are treated after 24 hours with different drugs indicated in each experiment in medium containing 1% FBS or lipoprotein deficient serum. Relative proliferation is determined using Cell Proliferation Assay Kit. Cells are incubated 1.5 hrs after adding tetrazolium salt WST-1 [2-(4-iodophenyl)-3- (4-nitrophenyl)-5-(2, 4-disulfo-phenyl)-2H-tetrazolium, monosodium salt] at 5% CO2, 37oC and the absorbance of the treated and untreated cells are measured using a microplate reader at 420 to 480 nm. Cells seeded in 12 well plates are counted using a hemocytometer, and dead cells are assessed using trypan blue exclusion assays.