Pathophysiology
- Destruction of dopaminergic neuronal cells in the substantia nigra in the basal ganglia.
- Degeneration of the dopaminergic nigrostriatal pathway.
- Depletion of dopamine store Imbalance of excitatory (acetylcholine) and inhibiting (dopamine) neurotransmitters in the corpus striatum.
- Impairment of extrapyramidal tracts controlling complex body movements.
- Tremors rigidity Bradykinesia
Discussion about etiology, hereditary and some genetic aspect in Parkinson’s disease
Etiology
Parkinson’s disease is caused by a loss of nerve cells in the part of the brain called the substantia nigra.
Nerve cells in this part of the brain are responsible for producing a chemical called dopamine.
Dopamine acts as a messenger between the parts of the brain and nervous system that help control and co-ordinate body movements.
If these nerve cells die or become damaged, the amount of dopamine in the brain is reduced.
This means the part of the brain controlling movement cannot work as well as normal, causing movements to become slow and abnormal.
The loss of nerve cells is a slow process. The symptoms of Parkinson’s disease usually only start to develop when around 80% of the nerve cells in the substantia nigra have been lost.
Hereditary
Some cases of Parkinson’s disease are hereditary, but this is rare.
This disease has been traced to different gene mutations. However, a strong family history of Parkinson’s disease can result in Young Onset Parkinson’s disease (YOPD) which occurs in people younger than 50 years of age.
Genetic
It is believed that Parkinson’s disease is caused by genetic mutations. Only 15 percent of those who have Parkinson’s disease have a family history of it.
Research suggests that a combination of genetic and environmental factors (exposure to pesticides, herbicides, chemicals & other toxins) may cause Parkinson’s disease.