IC50: 44 to 190 nM (ACAT)

E-5324 is a potent ACAT inhibitor with IC ₅₀ s of 44 to 190 nM in microsomes. E-5324 shows no effect on triglyceride synthesis up to 10 μM. E-5324 also has no effect on bovine pancreatic cholesterol esterase or lecithin: cholesterol acyltransferase (LCAT) up to 10 μM. E-5324 inhibits the incorporation of [ ³ H]oleate into cholesteryl [ ³ H]oleate in a concentration-dependent manner with an IC ₅₀ of 0.44 μM. E-5324 also inhibits [ ³ H]cholesteryl ester synthesis with an IC ₅₀ of 0.41 μM.

The areas under the cholesterol-time curves for duration of this study (AUC) for control, E-5324 0.02% and E-5324 0.1% are 104985±4411, 106096±4476 and 105231±4 348 mg×day/dL, respectively. The high dose of E-5324 (0.1%) significantly reduces the surface involvement by 34% and 54% in the aortic arch and thoracic aorta, respectively. E-5324 treatment significantly reduces the wet weight and protein content. In the aortic arch, the high dose of E-5324 (0.1%) significantly reduces both cholesteryl ester and total cholesterol by 60% and 59%, respectively. The high dose of E-5324 (0.1%) markedly reduces the ACAT activities in the aortic arch and thoracic aorta by 35% and 44%, respectively.