Robert Lefkowitz, investigator at the Howard Hughes Medical Institute and Duke University Medical Center, and Brian Kobilka of the Stanford University School of Medicine, were awarded the prize by the Royal Swedish Academy of Sciences on 9 October.
The academy awarded the prize for "ground-breaking discoveries that reveal the inner workings of an important family of... receptors: G-protein-coupled receptors".
Professor Lefkowitz's work, which began in the 1960s, used radioactive tracing to reveal several receptors and gain an initial understanding of how they worked.
Later Professor Kobilka was able to isolate the gene that codes for a specific adrenaline receptor, unearthed by Professor Lefkowitz's team, and show that it was linked it to a whole family of similarly functioning receptors.
Together the two scientists' work has shed light on how receptors allow cells to sense their environment, including light, flavour and odour and hormones. About half of all medications achieve their effect through this family of receptors.
Mark Downs, chief executive of the Society of Biology, said the work spanned genetics and biochemistry, and had laid the basis for "much of our understanding of modern pharmacology".
"Thus this is work at the biology/chemistry interface of great importance, and also with considerable impact in the broader sense," he said.
David Phillips, former president of the Royal Society of Chemistry, said the fact that both the 2012 Nobel Prizes for chemistry and medicine had been awarded to cell biologists showed "what an important role chemistry has to play in cell biology studies".