London:
An American scientist, Robert Furchgott, who shared the Nobel Prize in 1998 for his work that led to the development of the anti-impotency drug Viagra has died at the age of 92.
The BBC reported on Sunday that the scientist's family announced that he died Tuesday in Seattle.
Furchgott shared a Nobel Prize in 1998 for work showing that the gas nitric oxide played an important role in the cardiovascular system.
The discovery that the gas could help enlarge blood vessels was a factor in the development of Viagra by the US pharmaceutical company Pfizer.