Deoxycorticosterone Acetate食塩高血圧ラットにおける一酸化窒素の役割

抄録

The relationship between nitric oxide (NO) and blood pressure (BP) in deoxycorticosterone acetatesalt hypertensive rats (DOC) was investigated. Although urinary NO₂^- +NO₃^- (NOx) excretion (UNOXV) increased 2 weeks after surgery (2W-DOC), UNOXV decreased 4 weeks after surgery (4W-DOC) compared with that of the control. BP and UNOxV did not change in DOC after treatment with L-arginine (Arg-DOC) . Aorta from 4W-DOC and Arg-DOC had significantly decreased relaxation responses to acetylcholine.Deendothelialized aorta from 4W-DOC and Arg-DOC had significantly decreased relaxation responses to lipopolysaccharide. These data suggest that : 1) transient increase of NO synthesis is accompanied by elevation of BP, but long-term elevation of BP decreases NO synthesis in endothelium and smooth muscle cells ; 2) L-arginine supplement has no effect on the development of hypertension nor on NO production by endothelium and smooth muscle cells in DOC.