Nicotine-induced adrenal beta-arrestin1 upregulation mediates tobacco-related hyperaldosteronism leading to cardiac dysfunction

Figure 2 Effect of tobacco compounds on AngII-dependent aldosterone synthesis and secretion in adrenocortical zona glomerulosa cells. A: Aldosterone secretion into the culture medium from H295R cells in response to a 6-hour-long 100 mmol/L AngII challenge, as measured 24 h post-treatment with 10 μmol/L nicotine or 10 μmol/L cotinine or vehicle (DMSO). Data are expressed as % of the AngII response in DMSO-treated cells. ^aP < 0.05, vs DMSO; n = 5 independent measurements per treatment performed in duplicate; B: StAR mRNA levels in H295R cells treated for 24 h with 10 μmol/L nicotine (Nic) or 10 μmol/L cotinine (Cot) or vehicle (DMSO). C-D: Protein levels in H295R cells treated for 24 h with 10 mol/L nicotine (Nic) or 10 μmol/L cotinine or DMSO. Representative western blots are shown in (C), along with glyceraldehyde 3-phosphate dehydrogenase as loading control, and the densitometric quantitation of three independent cell extracts per condition run in duplicate (and normalized to glyceraldehyde 3-phosphate dehydrogenase) is shown in (D). ^aP < 0.05, vs DMSO; n = 3 independent experiments/treatment in duplicate. DMSO: Vehicle; Cot: Cotinine; Nic: Nicotine; GAPDH: Glyceraldehyde 3-phosphate dehydrogenase.