Sigmon D H, Beierwaltes W H
Hypertension and Vascular Research Division, Henry Ford Hospital, Detroit, MI 48202-2689.
J Am Soc Nephrol. 1994 Dec;5(6):1369-77. doi: 10.1681/ASN.V561369.
Endothelium-derived nitric oxide (EDNO) maintains RBF in normal kidneys and to the nonclipped kidney of two-kidney, one-clip (2K, 1C) renovascular hypertensive rats. However, in clipped kidneys with severe renal stenosis, EDNO has been reported not to influence RBF, and it was suggested that low perfusion diminishes the stimulus of shear stress for EDNO synthesis. It was hypothesized that lesser degrees of renal artery stenosis would allow greater renal perfusion and, hence, a greater role for EDNO in maintaining RBF in the clipped kidney. The renal response to EDNO synthesis inhibition was studied with 10 mg/kg body wt N omega-nitro-L-arginine methyl ester (L-NAME). Four weeks after clipping, rats had different degrees of (functional) renal artery stenosis as determined by the ratio (R) of RBF (per gram kidney weight) in the nonclipped to clipped kidney. Stenosis was classified as either mild (R < or = 1.25) or moderate (R > or = 1.30). Both groups were similarly hypertensive (146 +/- 3 versus 148 +/- 6 mm Hg, respectively) and responded to L-NAME with a 42 mm Hg rise in blood pressure. In 2K,1C rats with mild renal artery stenosis, the renal response to L-NAME was similar in both nonclipped and clipped kidneys. RBF decreased by 17 to 19% (P < 0.005) and renal vascular resistance (RVR) increased by 59 to 63% (P < 0.005). When renal perfusion pressure was controlled, the decrease in RBF was exaggerated 3.6-fold in the nonclipped but only 2.3-fold in the clipped kidney, whereas the RVR increased proportionally.(ABSTRACT TRUNCATED AT 250 WORDS)
内皮衍生的一氧化氮（EDNO）可维持正常肾脏以及两肾一夹（2K，1C）肾血管性高血压大鼠未夹闭肾脏的肾血流量（RBF）。然而，据报道，在严重肾狭窄的夹闭肾脏中，EDNO并不影响RBF，有人认为低灌注会减少EDNO合成的剪切应力刺激。据推测，较轻程度的肾动脉狭窄会使肾脏灌注增加，因此，EDNO在维持夹闭肾脏的RBF方面作用更大。用10mg/kg体重的Nω-硝基-L-精氨酸甲酯（L-NAME）研究了肾脏对EDNO合成抑制的反应。夹闭四周后，根据未夹闭肾脏与夹闭肾脏的肾血流量（每克肾脏重量）之比（R），大鼠有不同程度的（功能性）肾动脉狭窄。狭窄分为轻度（R≤1.25）或中度（R≥1.30）。两组血压相似（分别为146±3和148±6mmHg），对L-NAME的反应是血压升高42mmHg。在轻度肾动脉狭窄的2K，1C大鼠中，未夹闭和夹闭肾脏对L-NAME的肾脏反应相似。RBF下降17%至19%（P<0.005），肾血管阻力（RVR）增加59%至63%（P<0.005）。当控制肾灌注压时，未夹闭肾脏的RBF下降幅度增大3.6倍，而夹闭肾脏仅增大2.3倍，而RVR则成比例增加。（摘要截短于250字）
