Greengard, Paul (1925-) shared the 2000 Nobel Prize in physiology or medicine for his discovery of how dopamine and a number of other transmitters in the brain exert their action in the nervous system.
Greengard was born in New York City on Dec. 11, 1925. In 1948, he graduated from Hamilton College in Clinton, New York. He earned M.D. and Ph.D. degrees from Johns Hopkins University in Baltimore in 1953. Greengard taught at Albert Einstein College of Medicine, New York City, and Yale University in New Haven, Connecticut. Since 1983, he served as professor and head of the Laboratory of Molecular and Cellular Neuroscience at Rockefeller University in New York City. Greengard married the sculptor Ursula von Rydingsvard and lives in New York City.
For many of his years of research, Greengard studied the action of dopamine, one of a group of chemicals called neurotransmitters, which carry information from one neuron (nerve cell) to another. By the 1960's, the existence of dopamine was known, but scientists did not know how it worked.
Greengard found that dopamine sets off a series of reactions within neurons (nerve cells) that have structures called dopamine receptors on their surface. When one neuron releases a neurotransmitter from its ending, a second neuron receives this chemical and responds by producing an electrical signal. This form of communication between two nerve cells is known as signal transduction.
Scientists believe that a disruption in signaling by the neurotransmitter dopamine is associated with several neurological and psychiatric disorders, such as Parkinson disease, schizophrenia, and attention deficit hyperactivity disorder. Greengard's discoveries have helped scientists develop drugs to treat these disorders.
Greengard shared the Nobel Prize with scientists Arvid Carlsson of Sweden and Austrian-born American Eric Richard Kandel for their discoveries on the chemical workings of the brain.