Parkinson's Disease is a progressive disorder that causes problems with movement, including tremor, muscle rigidity and slowness. Around 120,000 people in the UK have this debilitating disease.
Parkinson's Disease is caused by the death of nerve cells in the brain, and gets worse as more nerve cells die. Doctors still don't know why Parkinson's disease develops, and there is no cure, but there have been advances in the past 40 years in the way it can be treated and controlled.
In the late 1950s, a Swedish scientist discovered a catecholamine called dopamine and, through research using rabbits, found that this could 'unlock' animals suffering from a form of sleeping sickness. Using this research, a Greek scientist working in the USA found that giving levodopa (L-dopa), which the brain coverts to dopamine, can relieve the symptoms of Parkinson's disease. This is regarded by the Parkinson's Disease Society as the 'gold standard' of drug treatments for Parkinson's. But about half of all patients suffer a severe recurrence of their symptoms within five years of starting L-dopa.
Stereotactic surgery, used to guide electrodes deep into the brain, was developed 100 years ago. It was used in more recent research on monkeys, resulting in a surgical treatment called deep brain stimulation (DBS) for Parkinson's disease. DBS uses a surgically implanted, battery-operated medical device called a neurostimulator - similar to a heart pacemaker - to deliver electrical stimulation to targeted areas in the brain that control movement.
Monkey research identified a potential target for DBS: a structure in the brain known as the subthalamic nucleus (STN). Continuous stimulation delivered by a wire inserted into the STN, and driven by a battery stimulator implanted under the collarbone, blocks the abnormal nerve signals that cause tremor and other Parkinson's symptoms.
This is powerfully demonstrated in this video of Parkinson's disease sufferer Mike Robbins.
DBS has transformed the lives of more than 40,000 PD patients. Unlike earlier surgical techniques, it does not destroy brain tissue, so it can be reversed if scientists develop better treatments in future.
For more information, see the AnimalResearch.info page on Parkinson's Disease.