RBP4 induces inflammation and hypertrophy in cardiomyocytes via activating TLR4. A, Tlr4 and Myd88 mRNA expression after treatment with RBP4 (50 μg/mL) or vehicle control for 48 hours. B and C, Cardiomyocytes were pretreated with TLR4 inhibitor (3 μM for 6 h), and then recombinant mouse RBP4 was added (50 μg/mL for 48 h). B, mRNA expression of Tnf-α, Il-6, Mcp-1, and Il-1β. C, mRNA expression of Anp, Bnp, and Myh7 (n = 6 per group). *, P < .05 vs control; #, P < .05 vs RBP4 alone. AU, arbitrary units.