Does the arteriovenous fistula in chronic haemodialysis patients stimulate endothelin-1 release?
Plasma endothelin-1 (ET-1)-like immunoreactivity was measured by radioimmune assay in predialysis plasma samples from 16 chronic haemodialysis patients (7 dialysing through arteriovenous (AV) fistulae and 9 using central venous cannulae for access), from 10 patients with functioning renal transplants (5 with AV fistulae and 5 without), and from 6 healthy subjects as controls. Among dialysis patients, ET-1 was greater in those with AV fistulae than in those using cannulae for dialysis (median (range), 5.5 (3.1) pM versus 3.7 (2.0) pM, P = 0.02), and in all haemodialysis patients ET-1 values were substantially greater than in normal controls (3.9 (3.2) pM versus 0.5 (0.1) pM; P = 0.001). In patients with functioning AV fistulae, ET-1 concentrations obtained directly from the AV anastomosis of the fistula (4.4 (3.0) pM) were less than those taken simultaneously from the contralateral arm (5.5 (3.1) pM; P = 0.04), while samples drawn from the venous side of the fistula were intermediate (4
