Washington — Two U.S. physicians won the 2012 Nobel Prize in Chemistry October 10 for their studies of protein receptors that enable body cells to sense and respond to outside signals.

Dr. Robert Lefkowitz of the Howard Hughes Medical Institute (HHMI) and Duke University Medical Center and Brian Kobilka of the Stanford University School of Medicine have both received long-term backing for their work from the U.S. National Institutes of Health (NIH).

A congratulatory press release from NIH reports that the agency has granted Lefkowitz about $15 million in government funding over more than a 30-year period of research. Kobilka, who collaborated with Lefkowitz, has received more than $14 million in U.S. support. The two worked to identify cellular processes that allow development of targeted medications, which reach the cells through these G-protein-coupled receptors (GPCRs).

“About half of all medications, including beta blockers, antihistamines and various kinds of psychiatric medications, act through these receptors,” said NIH Director Francis Collins. “NIH is proud to have supported this work, which began as basic science and ultimately led to dramatic medical advances.”

After the announcement, Lefkowitz said at a news conference at Duke in Durham, North Carolina, that defining these cell receptors has been his life’s work, dating back to a fellowship at NIH in 1968.

“When I started, there was a lot of skepticism about whether such receptors even existed, and there was no way to study them,” said Lefkowitz.

The existence of these receptors as cell sensors was only theorized through most of the 20th century. In the early 1980s, Lefkowitz was the first to isolate the receptors and identify the amino acids.

Our bodies rely on about 1,000 of these receptors, playing crucial roles in the function of smell, sight and taste, as well as regulating bodily functions of heart rate, blood pressure and glucose metabolism.

What Kobilka did, Lefkowitz said, is take the early work further, to see the proteins, “literally, atom by atom.”

“I hope my discovery leads to better and less expensive drugs for patients,” Kobilka said in a Stanford University press release.

“The NHLBI [National Heart, Lung and Blood Institute] is proud to have supported these researchers, whose work continues to yield promising insights into improving public health,” said Dr. Gary Gibbons, director of NHLBI, which directly funded the Lefkowitz-Kobilka work.

Lefkowitz said in an HHMI press release that he isn’t finished yet. “I come to work every day with a sense of great anticipation and curiosity about what new discoveries and insights will come our way,” he said. “Every question that we can answer poses several new ones that seem even more interesting than the one we’ve just answered.”