RELATIONSHIP BETWEEN OBSTRUCTION OF ARTERIOVENOUS-FISTULA AND PLASMA-LEVEL OF ENDOTHELIN-1 IN LONG-TERM HEMODIALYSIS-PATIENTS

The relationship between the patency status of the autogenous arteriov enous (A-V) fistula and the plasma level of endothelin-1 (ET-1) was st udied in 41 patients who had been receiving routine long-term haemodia lysis for more than 10 years. The ET-1 level in the haemodialysis pati ents (mean +/- s.d. = 2.1 +/- 0.9 pg/mL) was significantly elevated co mpared with that in healthy controls (n = 16; 1.1 +/- 0.4 pg/mL; P < 0 .01). The patients were classified into two groups according to whethe r the original A-V fistula had remained patent for more than 10 years or had been repaired due to frequent (more than twice) obstruction. Am ong all 41 patients, 21 were receiving recombinant human erythropoieti n (rHuEpo) intravenously (i.v.). In the rHuEpo-treated group, the plas ma ET-1 (n = 21; 2.4 +/- 0.8 pg/mL) was significantly elevated than th at in the rHuEpo-untreated group (n = 20; 1.9 +/- 0.9 pg/mL; P < 0.05) . After exclusion of the 21 rHuEpo-treated patients, the ET-1 level in the repaired fistula group (n = 11; 2.3 +/- 0.9 pg/mL) was significan tly higher than that in the patent original fistula group (n = 9; 1.3 +/- 0.7 pg/mL; P < 0.02). Based on these results, we conclude that ET- 1 shows a close relation to venous stenosis of the A-V fistula which m ay be due to its vasoconstrictive and smooth muscle cell-proliferating effects.