title: Imbalance of renal production between 5-hydroxytryptamine and dopamine in patients with essential hypertension complicated by microalbuminuria.
abstract: BACKGROUND
  In the kidney, 5-hydroxytryptamine (5-HT) and dopamine (DA) are formed by the same enzyme, l-aromatic amino acid decarboxylase, but act on renal function and glomerular structure in an opposite direction. The present study was designed to explore whether rates of renal production of 5-HT relative to that of DA are altered in patients with essential hypertension and microalbuminuria.
  
  
  METHODS
  We measured urinary levels of 5-HT and DA, reflecting renal production of 5-HT and DA as well as 24-hour ambulatory blood pressure and urinary albumin excretion in 82 consecutive untreated, essential hypertensives without overt proteinuria.
  
  
  RESULTS
  Urinary 5-HT excretion and the ratio of urinary 5-HT to DA were significantly higher in 22 patients with microalbuminuria than in the remaining patients with normoalbuminuria, although urinary DA levels did not differ between the groups. The 24-hour systolic and diastolic blood pressures were also higher in the microalbuminuric group than in the normoalbuminuric group. Multiple regression analysis revealed that urinary 5-HT excretion and 24-hour systolic blood pressure were independently associated with urinary albumin excretion. Furthermore, urinary 5-HT excretion was positively correlated with creatinine clearance as well as blood pressure but tended to be negatively correlated with fractional excretion of sodium.
  
  
  CONCLUSIONS
  Renal production of 5-HT is enhanced compared with that of DA in essential hypertensives with microalbuminuria. This imbalance may contribute to the genesis of hypertensive glomerular damage.
authors: Second Department of Internal Medicine, University of Toyama, Toyama,  Japan.
authors: Masayo
authors: M
authors: Hirose
authors: Fumihiro
authors: F
authors: Tomoda
authors: Tsutomu
authors: T
authors: Koike
authors: Hidenori
authors: H
authors: Yamazaki
authors: Maiko
authors: M
authors: Ohara
authors: Hexing
authors: H
authors: Liu
authors: Satoshi
authors: S
authors: Kagitani
authors: Hiroshi
authors: H
authors: Inoue
mesh_terms: D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000453:epidemiology* / Q000378:metabolism*; D001794:Blood Pressure / Q000502:physiology; D018660:Blood Pressure Monitoring, Ambulatory; D002940:Circadian Rhythm / Q000502:physiology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004298:Dopamine / Q000378:metabolism*; D000075222:Essential Hypertension; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000378:metabolism* / Q000503:physiopathology; D007668:Kidney / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012701:Serotonin / Q000378:metabolism*
chemical_list: D012701:Serotonin; D004298:Dopamine