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Analytical Techniques for Assaying Nitric Oxide Bioactivity
11:28

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Published on: June 18, 2012

Rate of reaction with nitric oxide determines the hypertensive effect of cell-free hemoglobin

D H Doherty1, M P Doyle, S R Curry

  • 1Somatogen, Inc. (now known as Baxter Hemoglobin Therapeutics, Inc.), Boulder, CO 80301, USA.

Nature Biotechnology
|July 14, 1998
PubMed

Administration of extracellular hemoglobin-based oxygen carriers often induces mild increases in blood pressure. In order to test whether nitric oxide (NO) scavenging is responsible for the hypertensive effect, we constructed and tested a set of recombinant hemoglobins that vary in rates of reaction with NO. The results suggest that the rapid reactions of oxy- and deoxyhemoglobin with nitric oxide are the fundamental cause of the hypertension. The magnitude of the blood-pressure effect correlates directly with the in vitro rate of NO oxidation. Hemoglobins with decreased NO-scavenging activity may be more suitable for certain therapeutic applications than those that cause depletion of nitric oxide.

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