Volume 61, Issue 6, Pages 1996-2005 (June 2002) Potentiation of [Ca2+]i response to angiotensin III by cAMP in cortical thick ascending limb  Annette Hus-Citharel, Jeannine Marchetti, Pierre Corvol, Catherine Llorens-Cortes  Kidney International  Volume 61, Issue 6, Pages 1996-2005 (June 2002) DOI: 10.1046/j.1523-1755.2002.00366.x Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 1 Representative recordings of intracellular Ca2+ levels elicited by 10−7 mol/L Ang II (A) or 10−7 mol/L Ang III (B) in the cortical thick ascending limb (CTAL) calculated from (N) individual determinations after 10 minutes of pretreatment with either vehicle alone (a1, b1) or 5 μmol/L forskolin (a2, b2). Each bar represents the mean data (±SEM): panel a3, (□) Ang II and (); Ang II + forskolin; panel b3, (□) Ang III and (▪) Ang III + forskolin. Δ[Ca2+]i is the variation in intracellular Ca2+ concentration expressed as a peak increase in [Ca2+]i above basal values. *P < 0.05, **P < 0.001. Kidney International 2002 61, 1996-2005DOI: (10.1046/j.1523-1755.2002.00366.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 2 Representative recording of intracellular Ca2+ levels elicited by 10−7 mol/L Ang II in the CTAL after 10 minutes of pretreatment with 5 μmol/L forskolin and 1 μmol/L losartan followed by a subsequent application of 10−7 mol/L bradykinin also performed in the presence of losartan. Kidney International 2002 61, 1996-2005DOI: (10.1046/j.1523-1755.2002.00366.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 3 Effects of forskolin treatment on dose-response curve of Ang III-induced Ca2+ mobilization. CTAL were superfused either in the presence of vehicle alone (•) or 5 μmol/L forskolin for 10min (○) and then exposed to various concentrations of Ang III. Each point represents the mean calculated from 5 to 16 individual determinations. Δ[Ca2+]i is the variation in intracellular Ca2+ concentration expressed as a peak increase in [Ca2+]i above basal values. *P < 0.05, **P < 0.01 when compared to control curve. Kidney International 2002 61, 1996-2005DOI: (10.1046/j.1523-1755.2002.00366.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 4 Effects of forskolin treatment on various doses of Ang III-induced Ca2+ mobilization in Ca2+-free medium. CTAL were superfused in the absence of external Ca2+ either in the presence of vehicle alone, control (□) or 5 μmol/L forskolin for 10min () and then exposed to three different concentrations of Ang III. Each bar represents the mean calculated from (N) individual determinations and the data are expressed as the mean ± SEM. Δ[Ca2+]i is the variation in intracellular Ca2+ concentration expressed as a peak increase in [Ca2+]i above basal values. *P < 0.05, **P < 0.01 when compared to control. Kidney International 2002 61, 1996-2005DOI: (10.1046/j.1523-1755.2002.00366.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 5 Representative recordings of intracellular Ca2+ levels elicited by 10−7 mol/L Ang III in the CTAL after 10 minutes of pretreatment with either vehicle alone (A) or 10−7 mol/L AVP (B). The mean ± SEM values are shown in panel C for AVP (), Ang III (□), and the theoretical () and experimental (▪) values for AVP + Ang III. Each bar represents the mean calculated value from (N) individual determinations. Δ[Ca2+]i is the variation in intracellular Ca2+ concentration expressed as a peak increase in [Ca2+]i above basal values. aStatistically different from the Δ[Ca2+]i obtained with either Ang III or AVP + Ang III (theoretical and experimental values). bStatistically different from the Δ[Ca2+]i obtained with AVP + Ang III (experimental values). cStatistically different from experimental values (one-way analysis of variance on weighted means followed by LSD Fisher's t test). a, b and cP < 0.001. Kidney International 2002 61, 1996-2005DOI: (10.1046/j.1523-1755.2002.00366.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 6 Model for AVP or forskolin-potentiates Ca2+ responses induced by Ang II/Ang III in CTAL. Dashed lines denote the putative pathways. Abbreviations are DAG, diacylglycerol; PKC, protein kinase C; InsP3-R, InsP3 receptor/channel; PDE, phosphodiesterase. Kidney International 2002 61, 1996-2005DOI: (10.1046/j.1523-1755.2002.00366.x) Copyright © 2002 International Society of Nephrology Terms and Conditions