Parkinson's Disease

Parkinson's Disease (PD) is a degenerative disease affecting the nervous system. The underlying cause is unknown, but symptoms appear when there is a lack of dopamine in the brain. Dopamine is a neurotransmitter that carries messages from one nerve cell to another. In healthy persons, it exists in balance with another neurotransmitter, acetylcholine. In people with what is called primary Parkinson's disease, the substantia nigra – the area of the brain containing cells that manufacture dopamine, noradrenaline, and serotonin – are damaged or dying, and the brain loses the ability to manufacture these chemicals.

The disease may start almost imperceptibly, with a mild, to moderate tremor of the hand or hands while at rest, a general slow and heavy feeling, muscular stiffness, bradykinesia (slowness of movement), and a tendency to tire more easily than usual. Later symptoms may include muscular rigidity; drooling; loss of appetite; a stooped, shuffling gait; tremors, including a characteristic “pillrolling” movement in which the thumb and forefinger rub against each other; impaired speech; and a fixed facial expression. The body gradually becomes rigid and the limbs stiffen. Depression and/or dementia may accompany the physical symptoms. While the cause of the loss of brain cells that causes Parkinson's disease remains unknown, a number of different theories have been developed. One hypothesis is that the cells are destroyed by toxins within the body that the liver is unable to filter out, metabolize, or detoxify because as the body ages, the liver loses its ability to work as effectively and as efficiently as it once did. Another theory is that exposure to environmental toxins, such as herbicides and pesticides that leach into ground water, is responsible.