title: Aldosterone and alterations of hypertension-related vascular function in African Americans.
abstract: BACKGROUND
  African Americans have a high prevalence of hypertension and hypertension-related vascular disease. We previously reported that plasma aldosterone concentrations are relatively high in hypertensive African Americans. This study evaluates the hypothesis that hypertension and hypertension-related alterations of peripheral vascular and renal vascular function are associated with aldosterone.
  
  
  METHODS
  Twenty four-hour blood pressures, cardiac output, renal blood flow (RBF), plasma renin activity (PRA), and plasma aldosterone were measured in hypertensive and normotensive African Americans. Hemodynamic measurements were repeated in response to graded infusions of norepinephrine (NE).
  
  
  RESULTS
  Ambulatory blood pressures in hypertensives and normotensives were 142 +/- 1/86 +/- 1 and 117 +/- 1/70 +/- 1 mm Hg, respectively. Cardiac index (CI) was lower (P < 0.01), peripheral vascular resistance was higher (P < 0.0001), arterial compliance was lower (P < 0.0001), RBF was lower (P = 0.04), and renal vascular resistance (RVR) was higher (P < 0.0001) in the hypertensives. Overall, blood pressures were positively correlated with peripheral vascular resistance (P < 0.0001) and inversely correlated with vascular compliance (P < 0.0001). In response to NE, hypertensives had greater increases of systolic blood pressure (P < 0.004) and pulse pressure (P < 0.005). PRA was lower (P < 0.0001) and plasma aldosterone was higher (P < 0.0001) in the hypertensives. Overall, blood pressures and pulse pressure were correlated with aldosterone (P < or = 0.01). Vascular compliance, RVR, and the increment of RVR in response to NE were also correlated with aldosterone (P < or = 0.03).
  
  
  CONCLUSIONS
  Aldosterone may contribute to hypertension and to hypertension-related alterations of peripheral vascular and renal vascular function in African Americans.
authors.affiliation: Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA. tkotchen@mcw.edu
authors.forename: Theodore A
authors.initials: TA
authors.lastname: Kotchen
authors.forename: Jane M
authors.initials: JM
authors.lastname: Kotchen
authors.forename: Clarence E
authors.initials: CE
authors.lastname: Grim
authors.forename: Shanthi
authors.initials: S
authors.lastname: Krishnaswami
authors.forename: Srividya
authors.initials: S
authors.lastname: Kidambi
mesh_terms: D000293:Adolescent; D000328:Adult; D001741:Black or African American; D000450:Aldosterone / Q000097:blood*; D000886:Anthropometry; D002302:Cardiac Output / Q000502:physiology; D002395:Catecholamines / Q000097:blood; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine; D012039:Regional Blood Flow / Q000187:drug effects; D012079:Renal Circulation / Q000187:drug effects; D012083:Renin / Q000097:blood; D013318:Stroke Volume / Q000502:physiology; D014662:Vasoconstrictor Agents
chemical_list: D002395:Catecholamines; D014662:Vasoconstrictor Agents; D000450:Aldosterone; D012083:Renin; D009638:Norepinephrine