[The role of nitric oxide in two-kidney, one-clip renovascular hypertensive rats].
The relationship between blood pressure(BP) and nitric oxide(NO) in two-kidney, one-clip renovascular hypertensive rats (2K1C) was investigated. Although urinary NO2- + NO3-(NOx) excretion (UNOX V) increased 2 weeks after surgery (2W-2K1C), UNOX V decreased 4 weeks after surgery (4W-2K1C) compared with that of the control. UNOX V levels were restored 2 weeks after unclipping (U2K1C). BP and UNOX V did not change in 2K1C after treatment with L-arginine (Arg-2K1C). Aorta from 4W-2K1C and Arg-2K1C showed significantly decreased relaxation responses to acetylcholine(Ach), but Ach-induced relaxation of aorta in U2K1C returned to control-level responses. De-endothelialized aorta from 4W-2K1C, Arg-2K1C, and U2K1C 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 and on NO production by endothelium and smooth muscle cells in 2K1C.
Yokokoji
K
K
Department of Cardiology, Surugadai Nihon University Hospital, Tokyo, Japan.
Otsuka
Y
Y
Okabe
T
T
Kanmatsuse
K
K
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000378:metabolism; D006978:Hypertension, Renovascular / Q000503:physiopathology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D009130:Muscle, Smooth / Q000378:metabolism; D009569:Nitric Oxide / Q000502:physiology*; D051381:Rats; D011921:Rats, Inbred WKY; D014664:Vasodilation / Q000187:drug effects
D008070:Lipopolysaccharides; D009569:Nitric Oxide; D000109:Acetylcholine