title: Urinary angiotensinogen as a marker of intrarenal angiotensin II activity in adolescents with primary hypertension.
abstract: BACKGROUND
  Experimental and epidemiological studies have demonstrated that urinary angiotensinogen (AGT) is a novel biomarker for the intrarenal activity of the renin-angiotensin system in hypertension (HT). Several large-scale epidemiological studies have shown that an elevated serum uric acid (SUA) level is associated with HT. The aim of our study was to assess urinary AGT excretion and its correlation with SUA level, the lipid profile, and the body mass index (BMI) Z-score in hypertensive adolescents.
  
  
  METHODS
  Participants were divided into two groups: (1) the group with confirmed HT consisting of 55 subjects with primary HT and (2) the reference (R) group consisting of 33 subjects with white-coat HT. A commercial enzyme-linked immunosorbent assay (ELISA) kit was used to determine urinary AGT concentration.
  
  
  RESULTS
  The urinary AGT/creatinine (cr.) ratio in subjects in the HT group was significantly higher than that in the reference group (p < 0.01) and showed a strong positive correlation with SUA (r = 0.47, p < 0.01). The relationship between the AGT/cr. ratio and SUA levels after controlling for age, gender and BMI Z-score continued to show a significant association.
  
  
  CONCLUSIONS
  The most obvious finding to emerge from this study is that in adolescents with primary HT, the increased urinary excretion of AGT correlated with hyperuricemia, although large, multicenter studies are needed to confirm this observation.
authors.affiliation: Department of Pediatrics and Nephrology, Medical University of Białystok, ul. Waszyngtona 17, 15-274 Białystok, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Kuroczycka-Saniutycz
authors.forename: Anna
authors.initials: A
authors.lastname: Wasilewska
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Sulik
authors.forename: Robert
authors.initials: R
authors.lastname: Milewski
mesh_terms: D000293:Adolescent; D000804:Angiotensin II / Q000378:metabolism*; D000808:Angiotensinogen / Q000652:urine*; D015415:Biomarkers / Q000097:blood / Q000652:urine; D015992:Body Mass Index; D016009:Chi-Square Distribution; D002648:Child; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D033461:Hyperuricemia / Q000097:blood / Q000175:diagnosis; D007668:Kidney / Q000378:metabolism*; D016014:Linear Models; D008055:Lipids / Q000097:blood; D008297:Male; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015854:Up-Regulation; D014527:Uric Acid / Q000097:blood
chemical_list: C534931:AGT protein, human; D015415:Biomarkers; D008055:Lipids; D000808:Angiotensinogen; D000804:Angiotensin II; D014527:Uric Acid; D003404:Creatinine