Is levodopa drugs the best option to fight parkinson's disease?
Introduction to parkinson’s disease
Parkinson’s disease is a neurodegenerative disease that affects the central nervous system. The cause of this gradual loss of neurone function is due to the lower production of dopamine ,which functions as a neurotransmitter,caused by the death of dopamine-generating cells in the brain. This means that nerve cells cannot operate as well meaning activities may take longer to complete. People with this disease show symptoms similar to that seen in parkinsonism. The primary symptoms involve difficulties with movement which could be observed as shaking or slowness of movement. Parkinsonism may be caused by the use of drugs. Although the symptoms are mainly physical difficulties having Parkinson’s disease also can cause psychiatric problems like dementia. With one in 500 people, the equivalent of 127,000 people in the UK, having parkinson’s disease it is one of the most common neurological diseases at the moment. It generally affects people around the age of 50+ and is more commonly found in men.
Parkinson’s in more detail
As mentioned before cells producing dopamine are destroyed and scientists currently believe that the main cause is due to genetic protein misfolding and build up. In Parkinson’s disease degeneration of the dopaminergic neurons producing dopamine means that lewy bodies form. This is when abnormal proteins develop inside nerve cells. The image on the right shows the difference of dopamine levels in a nerone between a healthy and Parkinson affected person. For an impulse to travel across synapses through the nervous system neurotransmitters are needed. They are released by vesicles and travel across the synapse to the receptors in the dendrite in an adjacent nerve cell where it recognises the neurotransmitter and continues the message by passing down the message in a similar way. In Parkinson’s disease the lack of dopamine means that there are fewer neurotransmitters crossing the synapse so the message understood at the receptors will be weaker or non-existent. This explains the slowness in movements or the resistance to movement.
Some of the symptoms that could be noticed is rigidity and bradykinesia. Rigidity is one of the hallmark symptoms of Parkinsons Disease where those who have it feel an increased resistance to motion. There are 2 main types of rigidity called cogwheel and lead pipe rigidity. Cogwheel rigidity means jerky resistance to movements as the muscles alternate between tensing and relaxing. Lead pipe rigidity is simply a more serious version of cogwheel rigidity where there’s more sustained resistance. In order to assess what stage of the disease the patient is at scientists use a classification table produced by Hoehn and Yahr and named as the classification of Disability as shown below.