Role of nitric oxide in hemodialysis-related hypotension in an experimental renal dysfunction dog model

To clarify the role of nitric oxide (NO) in hemodialysis (HD)-related hypotension, the relationship between plasma NO metabolites (NOx) and blood pressure changes, and the effect of NG-monomethyl-L-arginine (L-NMMA), a NO synthase inhibitor, on changes in blood pressure were evaluated in an experimental renal dysfunctional dog model. In order to create a renal dysfunction model, gentamicin was administered to male beagles in which 7 of 8 renal artery branches had been ligated. Normal renal functional and dysfunctional dogs underwent 3 hr of HD per day for 3 days. HD induced a transient decrease in mean blood pressure in the normal renal functional dogs. In renal dysfunctional dogs, a continuous hypotension occurred with a gradual increase in the plasma NOx concentration during HD. Although L-NMMA prevented the fall in blood pressure, it did not significantly change the plasma NOx concentration during HD. These results suggest that NO contributes to HD-related hypotension in renal dysfunctional dogs but the plasma NOx concentration does not reflect the change in blood pressure.