Efferent arteriole tubuloglomerular feedback in the renal nephron Yilin Ren, Jeffrey L. Garvin, Oscar A. Carretero  Kidney International  Volume 59, Issue 1, Pages 222-229 (January 2001) DOI: 10.1046/j.1523-1755.2001.00482.x Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 1 Orthograde perfusion of the efferent arteriole (Ef-Art), showing the effect of varying NaCl concentration at the macula densa on efferent arteriole diameter with and without preconstriction. In the absence of preconstriction (○), changing the NaCl concentration had no effect on diameter; however, when efferent arterioles were preconstricted by adding 1 μmol/L norepinephrine (NE; •) to the bath, increasing the NaCl concentration at the macula densa caused the efferent arterioles to dilate (*P < 0.001 vs. 17 Na/2 Cl with NE; N = 8). Kidney International 2001 59, 222-229DOI: (10.1046/j.1523-1755.2001.00482.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 2 (A) Retrograde perfusion of the efferent arteriole (Ef-Art), showing the effect of varying NaCl concentration at the macula densa on efferent arteriole diameter with and without preconstriction. In the absence of preconstriction (○), changing the NaCl concentration had no effect on diameter; however, when efferent arterioles were preconstricted by adding 1 μmol/L NE (•) to the bath, increasing the NaCl concentration at the macula densa caused the efferent arteriole to dilate (*P < 0.001 vs. 17 Na/2 Cl with NE; N = 8). (B) Time controls of efferent arterioles preconstricted with NE (N = 5). The arteriole constricted further when NaCl at the level of the macula densa was not increased, and this change in diameter was statistically significant. Kidney International 2001 59, 222-229DOI: (10.1046/j.1523-1755.2001.00482.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 3 Retrograde perfusion of the efferent arteriole (Ef-Art), showing the effect of varying NaCl concentration at the macula densa on efferent arteriole diameter in controls (○; N = 8) and treated with an adenosine A1/A2 receptor antagonist (PSPX; ▪; N = 11). *P < 0.001 vs. control. Kidney International 2001 59, 222-229DOI: (10.1046/j.1523-1755.2001.00482.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 4 Retrograde perfusion of the efferent arteriole (Ef-Art), showing the effect of varying NaCl concentration at the macula densa on efferent arteriole diameter in controls (○; N = 8) and treated with an adenosine A2 receptor antagonist (DMPX; ▪; N = 6). *P < 0.001 vs. control. Kidney International 2001 59, 222-229DOI: (10.1046/j.1523-1755.2001.00482.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 5 Retrograde perfusion of the efferent arteriole (Ef-Art), showing the effect of varying NaCl concentration at the macula densa on efferent arteriole diameter in controls (○; N = 8) and treated with an adenosine A1 receptor antagonist (FK838; N = 8). *P < 0.001 vs. 17 Na/2 Cl with NE. Kidney International 2001 59, 222-229DOI: (10.1046/j.1523-1755.2001.00482.x) Copyright © 2001 International Society of Nephrology Terms and Conditions