Tuesday, September 05, 2000
Parkinson's Affects the Heart Too
Parkinson's disease is typically perceived as a brain disorder that causes people to twitch and shake uncontrollably, but new research indicates the heart suffers too.
Scientists at the U.S. National Institute of Neurological Disorders and Stroke, a division of the National Institutes of Health, used positron emission topography (PET) to examine the hearts of 29 Parkinson's disease patients. They found that nearly all of the patients had damaged nerve endings around their heart. These nerve endings are responsible for producing a chemical called norepinephrine, which play a role in sending signals between nervous cells.
Such nerve-sending chemicals are vital to human functioning; the tremors Parkinson's patient suffer is caused by a decline in these nerve-transmitting chemicals.
Taking levodopa, a common Parkinson's disease medication, did not appear to affect the loss of nerve endings surrounding the heart, researchers report in the September 5 issue of Annals of Internal Medicine. Loss of these nerve endings near the heart is crucial since these nerve cells belong to the sympathetic nervous system, which helps control blood pressure, pulse, perspiration, and many other automatic responses to stress.
Since the heart appears affected by Parkinson's disease, researchers are now questioning whether other vital organs are also affected. Researchers speculate that a toxic chemical associated with Parkinson's disease may be causing these nerve endings to prematurely wear out. They conclude that more research is needed.
--By Katrina Woznicki