Monday, July 27, 2009 - 1:00 PM
S29

The Nitrite Reductase Activity of Cross-Linked Hemoglobin - Kinetic Enhancements from Addition of PEG Chains

Ronald Kluger and Francine Lui. Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5s 3H6, Canada

The conversion of nitrite to nitric oxide was found by Gladwin to be an important function of red cells that helps maintain blood vessels in their relaxed state due to the relaxation signal from NO. Addition of cross-linked hemoglobin as a red cell substitute leads to vasoconstriction related to scavenging of NO. Addition of PEG chains to hemolgobin appears to minimize vasoactivity in several cases. Kinetic analysis of the nitrite reductase activity of cross-linked hemoglobin with and without PEG shows that the PEG chains enhance the rate of conversion of nitrite to nitric oxide (while producing metHb), counteracting the effects of scavenging.


Web Page: www.chem.utoronto.ca/staff/RHK/kluger_r.html