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Blood Vessel Specific Vaso-Activity To Nitrite Under Normoxic And Hypoxic Conditions

  • Thomas E Ingram
  • Andrew G Pinder
  • Alexandra B Milsom
  • Stephen C Rogers
  • Dewi E Thomas
  • Philip E James
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 645)

Abstract

This study uses an organ chamber bioactivity assay to characterise the direct effect of sodium nitrite upon rabbit blood vessels (aorta (Ao), inferior vena cava (IVC) and pulmonary artery (PA)) in a haemoglobin independent/variable oxygen environment. In 95% oxygen constriction to 8g (Ao), 6g (PA) and 4g (IVC) was achieved using 1μM phenylephrine. The same constriction in 1% oxygen required 3μM. During 95% oxygen constriction was consistent and sustained for all vessels. However under 1% oxygen PA was quick to constrict but rapidly gave up this tension whereas Ao was slower to constrict but exhibited a more sustained response.

Relaxation of each vessel was assessed post constriction using 10μM sodium nitrite. Results were expressed as a percentage loss in tension compared to the maximum achieved and corrected by controls which received no nitrite. At 95% oxygen PA relaxed greater than Ao (10.04% ± 2.28% vs. 5.25% ± 1.51%). IVC response was varied (2.26% ± 9.43%). At 1% oxygen all vessels relaxed more. However the pattern was reversed with both IVC (14.20% ± 3.63%) and PA (16.55% ± 0.93%) relaxing less than Ao (42.20% ± 5.21%). These results suggest that relatively low concentrations of sodium nitrite can vasodilate blood vessels. This effect is independent of haemoglobin and tissue specific.

Keywords

Pulmonary Artery Inferior Vena Cava Sodium Nitrite Arterioscler Thromb Vasc Biol Potassium Nitrite 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    J. O. Lundberg and E. Weitzberg, NO Generation From Nitrite and Its Role in Vascular Control, Arterioscler Thromb Vasc Biol. 25, 915-922 (2005).PubMedCrossRefGoogle Scholar
  2. 2.
    E. Reichart and S. Mitchell, On the physiological action of potassium nitrite, Amer J Med Sci. 154, 158-180 (1880).CrossRefGoogle Scholar
  3. 3.
    R. F. Furchgott and S. Bhadrakom, Reactions of strips of rabbit aorta to epinephrine, isopropylarterenol, sodium nitrite and other drugs, J Pharmacol ExpTher. 108, 129-143 (1953).Google Scholar
  4. 4.
    K. Cosby and M. T. Gladwin, Nitrite reduction to nitric oxide by deoxyhemoglobin vasodilates the human circulation, Nat med. 9, 1498-1505 (2003).PubMedCrossRefGoogle Scholar
  5. 5.
    A. R. Maher, P. E. James and M. P. Frenneaux, Hypoxic modulation of exogenous nitrite induced vasodilation in man, In press(2007).Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Thomas E Ingram
    • 1
  • Andrew G Pinder
  • Alexandra B Milsom
  • Stephen C Rogers
  • Dewi E Thomas
  • Philip E James
  1. 1.Department of Cardiology Wales Heart Research Institute, University of CardiffUnited Kingdom

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