In:
Kidney and Blood Pressure Research, S. Karger AG, Vol. 25, No. 1 ( 2002), p. 42-49
Abstract:
〈 i 〉 Background: 〈 /i 〉 Nitric oxide (NO) plays an important role in the regulation of blood pressure and renal hemodynamics. 〈 i 〉 Methods: 〈 /i 〉 To further investigate the role of NO in human hypertension, we studied the effect of systemic injection of N 〈 sup 〉 G 〈 /sup 〉 -monomethyl- 〈 i 〉 L 〈 /i 〉 -arginine (L-NMMA) on renal hemodynamics, urinary sodium excretion (FE 〈 sub 〉 Na 〈 /sub 〉 ), systemic hemodynamics and several vasoactive hormones in 5 healthy male subjects with (group H) and without (group N) family history of hypertension. An intravenous infusion of L-NMMA (3 mg/kg over 10 min) or placebo was given in a randomized, double-blinded manner. GFR and ERPF were measured by inulin- and PAH-clearances. Norepinephrine infusion (0.1 µg/kg/min over 60 min) served as vasoconstrictive control infusion. 〈 i 〉 Results: 〈 /i 〉 L-NMMA induced a significant decrease in ERPF (–135 ± 49 vs. 7 ± 31 ml/min/1.73 m 〈 sup 〉 2 〈 /sup 〉 with placebo, p 〈 0.05), a decrease in FE 〈 sub 〉 Na 〈 /sub 〉 (–1.2 ± 0.6% with L-NMMA vs. 0.0 ± 0.1% with placebo), and a significant increase in diastolic blood pressure (+7 ± 1 vs. –2 ± 1 mm Hg with placebo) in group N, only. A sustained drop in plasma renin activity (–0.1 ± 0.1 vs. 0.3 ± 0.1 ng/ml/h with placebo) could also be seen in this group, only. Subjects with family history of hypertension showed minor or even no response (changes in diastolic blood pressure: L-NMMA: 5 ± 3 mm Hg, placebo: 0 ± 2 mm Hg; changes in ERPF: L-NMMA: –89 ± 57 ml/min/1.73 m 〈 sup 〉 2 〈 /sup 〉 , placebo: –34 ± 28 ml/min/1.73 m 〈 sup 〉 2 〈 /sup 〉 ; changes in plasma renin activity: L-NMMA: –0.0 ± 0.3 ng/ml/h, placebo: –0.1 ± 0.2 ng/ml/h). The vasoconstrictive effect of norepinephrine infusion did not differ between both groups. 〈 i 〉 Conclusion: 〈 /i 〉 Our data indicate that systemic NO synthetase inhibition by L-NMMA results in a blunted effect on systemic blood pressure and the renal hemodynamic system in subjects with family history of hypertension.
Type of Medium:
Online Resource
ISSN:
1420-4096
,
1423-0143
Language:
English
Publisher:
S. Karger AG
Publication Date:
2002
detail.hit.zdb_id:
1482922-8
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