Multidrug resistance-associated protein 4 regulates cAMP-dependent signaling pathways and controls human and rat SMC proliferation
J. Clin. Invest. Yassine Sassi, et al. 118:2747 doi:10.1172/JCI35067 [Go to this article.]

Figure 5
Effect of MRP4 siRNA on cAMP and cGMP cellular levels. Intracellular/extra­cellular ratios of (A) cAMP and (B) cGMP, measured with a specific competitive enzyme immunoassay, in hCASMCs transfected with scrambled, MRP5, or MRP4 siRNAs for 72 h and in hCASMCs treated with IBMX (100 μM, 24 h) in the presence or absence of MRP4 siRNA (for 72 h). n = 3. (C) Relative levels of MRP4 mRNA normalized to RPL32 mRNA (*P < 0.05) and (D) MRP4 protein normalized to PP2B in cells untreated or treated with IBMX (100 μM, 24 h). Western blot shows expression of MRP4 and PP2B in hCASMCs untreated or treated with IBMX. *P < 0.05, **P < 0.01, ***P < 0.001.