Our movements are controlled by nerve cells in the brain. To prompt a movement, the cells pass messages to one another - and to the rest of the body - using neurotransmitters. In Parkinson’s, these messages are disrupted and are not transmitted smoothly to the muscles, resulting in difficulties controlling movement.
The messages fail to transmit properly because of a lack of dopamine - one of the neurotransmitters involved in the control of movement. In people with Parkinson’s, between 70% and 80% of the cells which produce dopamine have degenerated and been lost. This occurs mainly in a small section of the brain called the substantia nigra. If there is insufficient dopamine, nerve cells do not function properly and are unable to pass on the brain messages, resulting in Parkinson’s symptoms.
While dopamine is the main neurotransmitter affected, other neurotransmitter abnormalities also occur. This is one explanation why simply replacing dopamine does not necessarily result in the benefits expected. The abnormalities in other neurotransmitters may also explain why so many non-motor symptoms are present in Parkinson’s.
Why dopamine-producing cells become depleted is not clear. It is generally thought that multiple factors are responsible and areas of current research include ageing, genetic and environmental factors, and viruses. It is also unclear why some people develop Parkinson’s but not others.
Did you know?
Parkinson’s disease was named after James Parkinson, the London doctor who first reported the symptoms in 1817, calling it the ‘shaking palsy’. It was his pioneering work in identifying and describing the disease that brought it to the attention of the medical profession. It has been known for hundreds of years although the condition wasn’t called Parkinson’s until the 19th century. In the ancient Indian medical system of Ayurveda it was called ‘Kampavata’.
Breaking point
You can make it
said one person
You deal with it so good
said another
You are doing so well
said a third
Sure, sure
I can take everything,
anything
And so I met one person
that said
‘How are you?’
Then the dam broke
Poem written 1998
Birgitta, 64
Jönköping, Sverige
