VASCULAR-RESPONSE TO VASOACTIVE AGENTS IN DIALYZED PATIENTS WITH CHRONIC-RENAL-FAILURE WITH AND WITHOUT DIABETES-MELLITUS

Using a muscle bath technique the vascular response to KCl, noradrenal ine, angiotensin II, acetylcholine, and sodium nitroprusside were eval uated in 13 patients with diabetes mellitus (DM group) and 15 nondiabe tic (non-DM group) chronic renal failure patients treated with haemodi alysis. There were no differences in age, duration of haemodialysis, b lood pressure and the levels of plasma renin activity, noradrenaline, and parathyroid hormone between groups. After informed consent was obt ained, a small piece of forearm vein was resected during the blood acc ess surgery. The ring preparation of the blood vessel was sustained in the muscle bath filled with Krebs-Henseleit solution and the isometri c tension development was recorded. All drugs produced concentration d ependent responses in the ring preparations of both groups. Although t here were no significant differences in E(max) values for KCl- and ang iotensin-II-induced contractions between groups, the value for noradre naline in the DM group was significantly less than that in the non-DM group. Sodium nitroprusside completely relaxed the ring preparation pr econtracted by 10(-5) M noradrenaline. However, the response to acetyl choline in the DM group was significantly weaker than that in the non- DM group. These results suggest a reduced vascular response to noradre naline and acetylcholine in dialysed diabetic renal failure patients, which may relate to the autonomic nervous system dysfunction.