By Ben Brumfield, CNN
updated 9:18 AM EDT, Wed October 10, 2012
(CNN) -- Two American scientists won the Nobel Prize in chemistry Wednesday for their work revealing protein receptors that tell cells what is going on in and around the human body. Their achievements have allowed drug makers to develop medication with fewer side effects.
Research spanning four decades by Robert J. Lefkowitz and Brian K. Kobilka on "G-protein-coupled receptors" has increased understanding of how cells sense chemicals in the bloodstream and external stimuli like light, according to the Royal Swedish Academy of Sciences, which awarded the prize.
Lefkowitz began the research by tracking adrenalin receptors. The Nobel Prize announcement apparently set off some of the excitement hormone in his own body.