Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0406810 (NAME)
 13,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Four chronic experiments were performed to assess changes in the activity and gene expression of type I nitric oxide synthase (NOS) at the macula densa (MD) and of renin expression and immunoreactivity (IR) at the juxtaglomerular apparatus (JGA) of rat kidney, as follows: 1) two-kidney, one-clip Goldblatt hypertension (2K1C, for 3 and 40 days; sham operation for controls), 2) furosemide treatment (150 mg/kg-1.day-1 ip for 5 days), 3) chronic low-salt diet (0.02%) vs. high-salt diet (3%; both for 11 days), and 4) chronic blockade of NOS by nitro-L-arginine methyl ester (L-NAME, 40 mg.kg-1.day-1 for 2 mo). NOS and renin gene expression, NOS enzyme activity and renin IR were semiquantitatively evaluated with histochemical methods (NADPH diaphorase, in situ hybridization, immunohistochemistry). In 2K1C, marked increases were induced in NOS and renin in the ischemic vs. contralateral kidneys both after 3 and 40 days, respectively (P < 0.05). Related to controls, significant increases in the ischemic kidney were encountered after 3 and 40 days, whereas contralateral suppression of NOS and renin was found only after 40 days. Furosemide treatment resulted in a marked increase of both NOS and renin levels compared with controls (P < 0.05). Salt restriction induced a significant elevation of NOS levels compared with salt loading (P < 0.05), whereas only minor changes were evident in renin levels. L-NAME treatment resulted in a moderate reduction of NOS activity (not significant), whereas renin levels were markedly reduced (P < 0.05). These results show that NOS activity and gene expression are inversely related to chronic changes in renal perfusion, salt balance, and salt transport at the distal tubule in parallel with the known response of renin to these changes. Inhibition of NOS decreases renin levels at the JGA. The histochemical findings support previous concepts that MD-derived NO is involved in the control of renin synthesis.
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PMID:Parallel regulation of constitutive NO synthase and renin at JGA of rat kidney under various stimuli. 859 73

Surgical correction of renal artery stenosis in Goldblatt hypertension rapidly normalizes blood pressure and increases renal function. This study was conducted in 1-kidney, 1 clip (1K1C) Goldblatt hypertensive rats to examine whether the unclipping-induced reversal of blood pressure and renal function is mediated by nitric oxide (NO). The 1K1C rats were prepared and given tap water with or without supplementation of NG-nitro-L-arginine methyl ester (L-NAME). Systolic blood pressure (SBP) before and after renal artery clipping was measured with the tail-cuff method. Four weeks later, surgical unclipping was performed while blood pressure and renal function responses were determined. The results show that clipping the renal artery for 4 weeks increased SBP from 140+/-5 to 183+/-6 mm Hg (P<0.05). Concurrent L-NAME treatment accelerated and aggravated the clipping-induced increases in SBP from 138+/-6 to 219+/-8 mm Hg (P<0.05). Surgical unclipping reduced blood pressure to normotensive levels within 2 hours in all hypertensive rats with and without chronic or acute L-NAME treatment. However, the magnitude of reductions in blood pressure in the initial 1 hour after unclipping was significantly less in L-NAME-treated rats than in nontreated rats (9+/-2% versus 16+/-1%, P<0.05). Despite reducing blood pressure, unclipping significantly increased glomerular filtration rate, urine flow, and sodium and potassium excretions, but the extent of the increases in these renal functions was significantly attenuated in L-NAME-treated rats. These data suggest that NO production partly contributes to the hypotensive and renal responses to unclipping but does not mediate the reversal of renovascular hypertension of this model.
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PMID:Nitric oxide synthesis inhibition retards surgical reversal of one-kidney Goldblatt hypertension in rats. 974 Jun 22

We examined the effect of acute systemic blockade of nitric oxide (NO) synthesis on blood pressure and renal function in rats with angiotensin II dependent two-kidney, one-clip Goldblatt hypertension. Hypertensive animals had significantly higher blood pressures, plasma NO metabolite concentrations and urinary NO metabolite excretion rates than control rats. Intravenous administration of N(G)-nitro-L-arginine methylester (L-NAME) (10 mg/kg) increased mean arterial pressure in both hypertensive and control animals with the magnitude of increase being greater in hypertensive than control rats (32 +/- 3 vs. 20 +/- 2 mmHg, p < 0.05). L-NAME did not affect glomerular filtration rates of normal and clipped kidneys but significantly decreased non-clipped kidney glomerular filtration rate (1.1 +/- 0.1 vs. 0.7 +/- 0.1 ml/min per g kidney wt, p < 0.05). Blood flow to normal and non-clipped kidneys fell in response to L-NAME. Percent reduction in renal blood flow produced by L-NAME was significantly greater in non-clipped than normal kidneys (38 +/- 3 vs. 24 +/- 2%, p < 0.05). In contrast, clipped kidney blood flow increased after L-NAME (3.3 +/- 0.2 vs. 4.0 +/- 0.2 ml/min per g kidney wt, p < 0.05). An identical improvement in clipped kidney blood flow occurred when arterial pressure was raised with aortic constriction indicating that the systemic pressor effect of L-NAME was responsible for this finding. These results indicate that NO plays an important role in systemic and non-clipped kidney hemodynamics in renovascular hypertension. Because NO has little influence on stenotic kidney function, the stimulus for increased NO system activity in this disease appears to be vascular shear stress rather than elevated circulating or intrarenal angiotensin II concentrations.
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PMID:Effect of nitric oxide inhibition on kidney function in experimental renovascular hypertension. 1133 92

Experiments were performed in male Sprague-Dawley rats (150-200 g). A silver clip (0.2 mm internal diameter) was placed on the left renal artery of rats. After operation the rats were divided into 4 groups sham group, 2K1C (two-kidney one clip) group, 2K1C+Arg (2K1C and L-Arg 150 mg/kg x d(-1) by drinking) group, and 2K1C+NAME (2K1C and L-NAME 10 mg/kg x d(-1) i.p.) group. The animals were studied at two time points (4 and 7 weeks after operation) corresponding to phases I and II of Goldblatt hypertension. The animals were deeply anesthetized with pentobarbital and perfused by the cardiac route with saline (100 ml) and freshly prepared 4% paraformaldehyde in phosphate buffer (300 ml). The caudal medulla was removed, then placed in 25% sucrose in PB for 12 h in a 4 degrees C fridge. The 40 microm coronal slices of brainstems were cut with cryostat, collected in PBS for nNOS study by immunohistochemistry. The results showed that (1) only a few neuronal nitric oxide synthase (nNOS) positive neurones were found in caudal medulla, including the depressor area of the ventral surface of medulla oblongata (VSMd) and the caudal pressor area (CPA) of the sham operated animals. The number of nNOS positive neurons in caudal medulla was significantly increased in 2K1C Goldblatt hypertension rats at 4 and 7 weeks. (2) The number of nNOS positive neurons in VSMd and CPA were 2K1C+Arg > 2K1C >2K1C +NAME > sham. (3) L-Arg enhanced the expression of nNOS whereas L-NAME inhibited the expression of nNOS in caudal medulla. (4) The character of nNOS expression was similar in Goldblatt hypertension rats at 4 weeks with that of the rats at 7 weeks.
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PMID:[The expression of neuronal nitric oxide synthase in caudal medulla of two-kidney one clip Goldblatt hypertension rat]. 1197 1