Renal BOLD-MRI relates to kidney function and activity of the renin-angiotensin-aldosterone system in hypertensive patients

J Hypertens. 2015 Mar;33(3):597-603; discussion 603-4. doi: 10.1097/HJH.0000000000000436.


Background: The renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system are key factors in the pathophysiology of hypertension. Renal hypoxia is the putative mechanism stimulating both systems. Blood oxygen level-dependent MRI (BOLD-MRI) provides a noninvasive tool to determine renal oxygenation in humans. The aim of the current study was to investigate the relation between blood pressure (BP) and kidney function with renal BOLD-MRI. Moreover, the relation between direct and indirect variables of the RAAS and sympathetic nervous system and renal BOLD-MRI was studied.

Method: Seventy-five hypertensive patients (38 men) were included. Antihypertensive medication was temporarily stopped. Patients collected urine during 24 h (sodium, catecholamines), blood samples were taken (creatinine, renin, aldosterone), a captopril challenge test was performed, and ambulatory BP was measured.

Results: Mean age was 58 (±11) years, day-time BP was 167 (±19)/102 (±16) mmHg, and estimated glomerular filtration rate was 75 (±18) ml/min per 1.73 m). In multivariable regression analysis, renal medullary R2*-values inversely related to estimated glomerular filtration rate (P = 0.02). Moreover, the BP-lowering effect of captopril positively related to cortical (P = 0.02) and medullary (P = 0.008) R2*-values, as well as to P90 (P = 0.02).

Conclusion: In patients with hypertension, kidney function relates to medullary R2*-values. Activation of the RAAS is also positively related to the renal R2*-values.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aldosterone / metabolism
  • Blood Pressure / physiology*
  • Creatinine / metabolism
  • Female
  • Glomerular Filtration Rate / physiology
  • Humans
  • Hypertension / physiopathology*
  • Kidney / physiopathology*
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Renin / blood
  • Renin-Angiotensin System / physiology*
  • Sodium / metabolism


  • Aldosterone
  • Sodium
  • Creatinine
  • Renin