|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
Watch the 2021 Nobel Prize lectures, the Nobel Prize Concert, Nobel Week Dialogue, the prize award ceremonies in Oslo and Stockholm and Nobel Peace Prize Forum here at nobelprize.org.