Luciferase assays were performed as described previously.21 (link) Briefly, cells grown in 6-well plates were transfected with an NF-κB firefly luciferase reporter plasmid 3X-κB-Luc (a gift from Dr. Hiroyuki Inuzuka) and a firefly luciferase reporter containing the IL-6 promoter (a gift of Dr. Hiroyuki Inuzuka) along with a pRL-CMV plasmid (Promega, Madison, WI, USA). After 24 h, cells were split into 96-well plates. After stimulation with aldosterone, firefly luciferase activity was measured using the Dual Luciferase Assay System and normalized to renilla luciferase activity according to manufacturer's instructions (Promega, Madison, WI, USA).