title: Endothelin-1 in continuous ambulatory peritoneal dialysis and hemodialysis patients: a preliminary study.
abstract: OBJECTIVE
  To determine the effects of continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) on endothelin-1 (ET-1) levels in patients with end-stage renal disease (ESRD) and to assess the relationship between plasma ET-1 levels and selected patient parameters.
  
  
  METHODS
  Prospective, nonrandomized comparison study.
  
  
  METHODS
  Outpatient CAPD and HD units of a university medical center.
  
  
  METHODS
  Twelve ESRD patients (6 on CAPD and 6 on HD) and 5 healthy normotensive subjects.
  
  
  METHODS
  CAPD patients had blood and peritoneal dialysate samples collected and measurements made following an overnight exchange. HD patients had blood collected and measurements made at 0 hours (basal) and again at 3 hours during a midweek HD session. Blood samples were also collected from normal subjects and served as ET-1 controls.
  
  
  METHODS
  ET-1 and patient parameters (creatinine, peritoneal dialysate volume, blood pressure, body weight, age, and treatment duration) were determined. Data are reported as the mean +/- one standard deviation.
  
  
  RESULTS
  Plasma and dialysate ET-1 levels in the CAPD group were 19.5 +/- 4.2 pg/mL and 9.2 +/- 4.2 pg/mL, respectively. The control group plasma and unused dialysate contained no detectable ET-1 (< 3.0 pg/mL, the limit of detection). The peritoneal clearance of ET-1 was less than that of creatinine (2.29 +/- 0.69 mL/minute vs 4.22 +/- 0.66 mL/minute, p = 0.005). The basal (0 hour) plasma ET-1 level in the HD group (16.5 +/- 7.8 pg/mL) did not differ from that of the CAPD group, p = 0.423. Furthermore, no differences in patient parameters were detected between the CAPD and basal HD groups. Although the mean arterial pressure (MAP) decreased during HD, the plasma ET-1 level at 3 hours (13.5 +/- 5.4 pg/mL) remained unchanged from the basal level, p = 0.307. An analysis of pooled data from the CAPD and HD groups revealed no significant correlation between plasma ET-1 and MAP, body weight, creatinine, or treatment duration. There was, however, a positive correlation between plasma ET-1 and age (r = 0.643, p = 0.024).
authors.affiliation: Department of Medicine, Medical College of Georgia, Augusta 30912-3140.
authors.forename: B O
authors.initials: BO
authors.lastname: Lightfoot
authors.forename: R J
authors.initials: RJ
authors.lastname: Caruana
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015314:Dialysis Solutions / Q000032:analysis; D016232:Endothelins / Q000032:analysis* / Q000097:blood; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory; D006435:Renal Dialysis
chemical_list: D015314:Dialysis Solutions; D016232:Endothelins