Inhibition of nitric oxide synthesis potentiates hypertension during chronic glucose infusion in rats

Christie R. Claxton, Michael W Brands, Sharyn M. Fitzgerald, Joseph A. Cameron

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Endothelial dysfunction has been proposed to contribute to impaired blood flow control or hypertension in many conditions characterized by hyperinsulinemia or hyperglycemia. However, most studies have focused on whether endothelial dysfunction is present in the established phases of these various hypertensive states, and there is little known concerning the role of the endothelium in the initial stages. This study tested whether nitric oxide production, before endothelial dysfunction develops, plays an important role in counteracting the hypertensive response to chronic glucose infusion. Glucose was infused (18.6 mg/kg per minute IV) for 7 days in 8 normal rats (G) and in 9 rats with a long-term background intravenous infusion of N(G)- nitro-L-arginine methyl ester (L-NAME) at 10 μg/kg per minute (G+L). Mean arterial pressure (MAP), measured 24 hours per day, increased an average of ≃11 mm Hg in the G rats. L-NAME treatment increased MAP an average of 28 ± 2 mm Hg in the G + L rats, and glucose infusion raised MAP >30 mm Hg above that, averaging 155 ± 8 mm Hg by day 6. In addition, heart rate increased from an average of 389 ± 8 bpm to 441 ± 16 bpm by day 6, whereas there was no significant change in the G rats. Glomerular filtration rate decreased significantly with L-NAME treatment and decreased in both groups by day 3 of glucose infusion, reaching lower levels in the G + L rats. These results show that NO is required to minimize the increase in MAP during glucose infusion and suggest that renal and neural mechanisms may be important in mediating that effect.

Original languageEnglish (US)
Pages (from-to)451-456
Number of pages6
JournalHypertension
Volume35
Issue number1 II
StatePublished - Jan 1 2000
Externally publishedYes

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Nitric Oxide
NG-Nitroarginine Methyl Ester
Hypertension
Glucose
Arterial Pressure
Hyperinsulinism
Glomerular Filtration Rate
Intravenous Infusions
Hyperglycemia
Endothelium
Heart Rate
Kidney
Therapeutics

Keywords

  • Blood pressure
  • Endothelium
  • Glomerular filtration rate
  • Insulin

ASJC Scopus subject areas

  • Internal Medicine

Cite this

Inhibition of nitric oxide synthesis potentiates hypertension during chronic glucose infusion in rats. / Claxton, Christie R.; Brands, Michael W; Fitzgerald, Sharyn M.; Cameron, Joseph A.

In: Hypertension, Vol. 35, No. 1 II, 01.01.2000, p. 451-456.

Research output: Contribution to journalArticle

Claxton, CR, Brands, MW, Fitzgerald, SM & Cameron, JA 2000, 'Inhibition of nitric oxide synthesis potentiates hypertension during chronic glucose infusion in rats', Hypertension, vol. 35, no. 1 II, pp. 451-456.
Claxton, Christie R. ; Brands, Michael W ; Fitzgerald, Sharyn M. ; Cameron, Joseph A. / Inhibition of nitric oxide synthesis potentiates hypertension during chronic glucose infusion in rats. In: Hypertension. 2000 ; Vol. 35, No. 1 II. pp. 451-456.
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