Ignarro’s spectral analysis

Louis Ignarro reported that EDRF relaxed blood vessels. He also identified EDRF as a molecule by using spectral analysis of hemoglobin. When hemoglobin was exposed to EDRF, maximum absorbance moved to a new wave-length; and exposed to NO, exactly the same shift in absorbance occurred! EDRF was identical with NO. A new principle for signalling between human cells was discovered.


 Hemoglobin (yellow) exposed to endothelial cells that were stimulated to produce EDRF (green)
 Hemoglobin (yellow) directly exposed to NO (green)

The shift of absorption curves is identical, hence EDRF is NO

To cite this section
MLA style: Ignarro’s spectral analysis. NobelPrize.org. Nobel Media AB 2019. Fri. 22 Feb 2019. <https://www.nobelprize.org/prizes/medicine/1998/7539-ignarros-spectral-analysis/>

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