title: Vasoactive hormones in uraemic patients with chronic hypotension.
abstract: BACKGROUND
  We evaluated the possible role of an imbalance between vasoconstrictor and vasodilator hormones in the pathophysiology of chronic hypotension in uraemia.
  
  
  METHODS
  Fourteen hypotensive haemodialysed patients, 14 normotensive haemodialysed patients, and 17 control subjects were included in this study. Plasma renin activity (PRA) and plasma levels of catecholamines, angiotensin II (AII), atrial natriuretic peptide (ANP), and arginine vasopressin (AVP) were measured.
  
  
  RESULTS
  The mean time on haemodialysis (HD) was longer in hypotensive patients than in normotensive patients (P < 0.01). Catecholamine levels were higher in the whole group of HD patients than in controls (P < 0.01). Catecholamine levels were higher in hypotensive patients than in normotensive patients, but the differences reached significance only for adrenaline (P < 0.05). PRA and plasma AII levels were higher in hypotensive patients than in the other two groups (P < 0.05), while no differences were observed between normotensive patients and controls. Plasma ANP and AVP levels were higher in HD patients than in controls (P < 0.01), but there were no differences between hypotensive and normotensive patients. In HD patients, mean blood pressure inversely correlated with PRA (r = -0.59, P < 0.01) and plasma AII levels (r = -0.80, P < 0.01).
  
  
  CONCLUSIONS
  Our results indicate that in HD patients with chronic hypotension there is an activation of the sympathetic and the renin-angiotensin systems. This activation is probably secondary in an attempt to compensate the vascular resistance to pressor stimuli reported in these patients.
authors.affiliation: Nephrology Unit, Hospital Clinic i Provincial, Barcelona, Catalonia, Spain.
authors.forename: N E
authors.initials: NE
authors.lastname: Armengol
authors.forename: A
authors.initials: A
authors.lastname: Cases Amenós
authors.forename: M
authors.initials: M
authors.lastname: Bono Illa
authors.forename: J
authors.initials: J
authors.lastname: Calls Ginesta
authors.forename: J
authors.initials: J
authors.lastname: Gaya Bertrán
authors.forename: F R
authors.initials: FR
authors.lastname: Rivera Fillat
mesh_terms: D000328:Adult; D000368:Aged; D000804:Angiotensin II / Q000097:blood; D001127:Arginine Vasopressin / Q000097:blood; D009320:Atrial Natriuretic Factor / Q000097:blood; D002395:Catecholamines / Q000097:blood; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007022:Hypotension / Q000097:blood* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D012083:Renin / Q000097:blood; D014511:Uremia / Q000097:blood* / Q000503:physiopathology
chemical_list: D002395:Catecholamines; D010281:Parathyroid Hormone; D000804:Angiotensin II; D001127:Arginine Vasopressin; D009320:Atrial Natriuretic Factor; D012083:Renin