Inhibition Assay: A test for MGAT2 inhibitory action of test compounds was conducted in accordance with a partially modified version of the method described in John F. Lockwood et al., Am. J. Physiol. Endocrinol. Metab., 2003, 285, E927.Bac-to-Bac Baculovirus Expression System (Life Technologies Japan) was used to express human MGAT2 in insect cells (Sf9) (Life Technologies Japan). These cells were sonicated and centrifuged at 100,000 g.times.1 hr to give a precipitate. The precipitate was used as a human MGAT2 enzyme fraction in this assay.This test was conducted using a black flat-bottom 96-well plate (Corning). A buffer solution with final concentrations of 5 mM magnesium chloride, 100 mM sucrose and 100 mM Tris-HCl (pH=7.5) was prepared and test compounds prepared in various concentrations using dimethyl sulfoxide were added thereto to give a final dimethyl sulfoxide concentration of 1%. The MGAT2 enzyme fraction was added thereto to give a final concentration of 0.5 .mu.g/ml.
Inhibition Assay: An MGAT2 inhibition test for test compounds was conducted in accordance with a partially modified version of the method described in John F. Lockwood et al., Am. J. Physiol. Endocrinol. Metab., 2003, 285, E927.A 10 mg/mL microsomal fraction of human small intestine (duodenum- and jejunum-derived fraction purchased from Becton Dickinson Japan) was used as an enzyme source.The test was conducted using a flat-bottom 96-well plate (Corning).A buffer solution with final concentrations of 5 mM magnesium chloride, 1.25 mg/ml bovine serum albumin and 100 mM Tris-HCl (pH=7.5) was prepared and the microsomal fraction of human small intestine was added thereto to give a final concentration of 5 .mu.g/ml. Test compounds prepared in various concentrations using dimethyl sulfoxide were added thereto to give a final dimethyl sulfoxide concentration of 1% and a reaction was performed at room temperature for 5 min.