April 15, 2005|
|
|
|
April 15, 2005 |
By Bill Fonda "In heart failure, (the) system is pretty messed up, basically," said Gregg, a Johns Hopkins University senior biomedical engineering student, of South Orleans, explaining why people who have had heart attacks often cannot exercise. Gregg said that the heart races when the nervous system releases neurotransmitters that attach to receptors in heart cells. Those receptors, in turn, cause the heart to contract harder. But, he added, different receptors are at work with those who have heart failure. Gregg knows this firsthand working in the lab of Johns Hopkins associate professor Dr. Dan Berkowitz under one of the university's Provost Undergraduate Research Awards. Gregg has been doing what Berkowitz called "ground-breaking research" on the heart's receptor cells. Gregg, a 2001 Nauset Regional High School graduate, whose family owns Bates Hardware in Harwich, originally started his research with what is called the beta-3 receptor. Unlike other receptors, it decreases how hard the heart beats when stimulated by neurotransmitters, and Gregg said it is common in people who have had heart attacks. "It seems like a protective measure," he said. "It's very difficult to find in a healthy heart." During his research, Gregg found a pathway to another receptor, where neurotransmitters regulate the heart's ability to contract. Basically, before his research, scientists thought there was only one receptor, that Gregg described as an "on switch." But there is also another receptor that acts as an "off switch." The research could be pivotal because doctors often prescribe beta blockers for people with heart disease. Those drugs, Gregg said, help prevent the brain from thinking the heart is being lazy, and shooting it messages to beat harder, when it can't because it's damaged. Now that the off switch has been discovered, scientists will need to see how the beta blockers are impacting the body's own ability to deal with conflicting internal messages. "This has important implications for people who have diseases in which the heart doesn't react properly," Berkowitz said. Gregg presented his findings to the American College of Cardiology's annual meeting in Orlando, Fla., last month. "I was there. He did a stellar job," Berkowitz said. Gregg said the Orlando meeting was a good way to keep in touch with clinical applications of heart treatment, as his work is basic cell biology that does not yet have any practical application. However, it does provide a better picture of how the heart works. Gregg became interested in researching heart receptors after taking a physiology class with Berkowitz during his junior year. Berkowitz said he "read him the riot act" and challenged him to read and understand literature on the subject before accepting him. "He was able to do that without any problem," Berkowitz said. "Chris is an incredibly smart kid." Gregg said he had to read for months in order to understand what everyone in the field was talking about. "I've gotten to the point where it's clear now and I can understand," he said. Gregg has been accepted into the doctoral programs both at Johns Hopkins and the University of California, San Diego. He said he is more likely to attend UCSD, studying the cellular foundations of disease. "I'm probably going to stick with the heart and heart disease and cardiovascular disease," he said. © Copyright of CNC and Herald Interactive Advertising Systems, Inc.
Find article online:
|
|
Return to today's news ...