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Updated: Jul 19, 2026
09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
Methemoglobin--it's not just blue: a concise review.
1PPD Inc., Wilmington, North Carolina 28412, USA. jay.umbreit@wilm.ppdi.com
American Journal of Hematology
|September 21, 2006
Summary
Hemoglobin and methemoglobin regulate vascular tone and inflammation through a redox couple. This process influences blood flow and contributes to cardiovascular damage and drug-induced methemoglobinemia.
Area of Science:
- Biochemistry
- Physiology
- Redox Biology
Background:
- Hemoglobin's primary role is oxygen transport.
- Hemoglobin also participates in redox reactions with methemoglobin.
- This redox couple influences vascular tone and inflammation.
Purpose of the Study:
- To elucidate the non-oxygen-carrying functions of hemoglobin.
- To explore the role of the hemoglobin-methemoglobin redox couple in physiological regulation.
- To understand the mechanisms linking methemoglobin to cardiovascular damage and drug interactions.
Main Methods:
- Analysis of the hemoglobin-methemoglobin redox couple.
- Investigation of nitrite reductase activity.
- Assessment of nitric oxide production in response to oxygen levels.
- Evaluation of methemoglobin-mediated oxidation of lipoproteins.
- Study of heme release in inflammatory processes.
- Review of drug-induced methemoglobinemia.
Main Results:
- The hemoglobin-methemoglobin couple acts as a nitrite reductase, producing nitric oxide to regulate vascular tone.
- Methemoglobin levels correlate with blood oxygen status.
- Methemoglobin contributes to arteriosclerosis via low-density lipoprotein oxidation.
- Heme released from methemoglobin is implicated in inflammation.
- This redox system is involved in drug metabolism leading to methemoglobinemia.
Conclusions:
- Hemoglobin possesses significant physiological functions beyond oxygen transport.
- The hemoglobin-methemoglobin redox couple is a key regulator of vascular tone and inflammation.
- Dysregulation of this system contributes to cardiovascular disease and adverse drug reactions.
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