Parkinsons Disease :: Biology Essays Research Papers

Parkinson's Disease Five years ago, she could still show the world her pleasant demeanor with a smile. Four years ago, she could no longer smile, but she was still able to walk upright. Two years ago, she could no longer walk without aid from a walker, but she could still find her mouth with a fork while eating dinner. Eighteen months ago, she could no longer eat under her own power, as the involuntary 'tremors' in her hands flung the food from the fork long before it reached her mouth. A year ago, my grandmother died. She was diagnosed with Parkinson's Disease (PD) five years ago, and slowly deteriorated for four years until her death. She was given myriad drugs, but none seemed to help for more than a month, leaving her in worse condition after the effects wore off. Herein lies the mystery of Parkinsonà ¢s Disease. Researchers have made great progress in uncovering the etiology of this mysterious disease. Before summarizing some of the current theories on the cause of PD, however, it is necessary to describe some clinical observations of patients. Symptoms of PD include "tremors," rigidity, bradikinesia (slowness of movement) and loss of postural control (1). It has been found that patients who show these symptoms for PD have an eighty percent reduction in the levels of both dopamine (a neurotransmitter in the Substantia Nigra) and dopaminergic neurons (neurons that contain dopamine receptors) (1). There are currently four main theories on the cause of Parkinson's Disease: (a) Oxidation of molecules such as iron in the Substantia Nigra by free radicals kill the dopaminergic neurons (1); (b) environmental toxins similar to MPTP (a compound related to the painkiller Demerol), which have been shown to cause Parkinsonism-like symptoms, kill the neurons (1,2); (c) a mysteriously increased rate of dopaminergic neuronal apoptosis in some individuals (1); and (d) Genetic influence, as the penetrance of PD has been observed at higher levels within some families (1). There is evidence for all of these theories, although the most concrete evidence comes from a study that showed increased levels of iron in the Substantia Nigra in PD patients (1). While this study proved nothing, it provided further evidence for a powerful oxidizing agent, such as a free radical, involved in the degeneration of dopaminergic neurons. Parkinson's Disease :: Biology Essays Research Papers Parkinson's Disease Five years ago, she could still show the world her pleasant demeanor with a smile. Four years ago, she could no longer smile, but she was still able to walk upright. Two years ago, she could no longer walk without aid from a walker, but she could still find her mouth with a fork while eating dinner. Eighteen months ago, she could no longer eat under her own power, as the involuntary 'tremors' in her hands flung the food from the fork long before it reached her mouth. A year ago, my grandmother died. She was diagnosed with Parkinson's Disease (PD) five years ago, and slowly deteriorated for four years until her death. She was given myriad drugs, but none seemed to help for more than a month, leaving her in worse condition after the effects wore off. Herein lies the mystery of Parkinsonà ¢s Disease. Researchers have made great progress in uncovering the etiology of this mysterious disease. Before summarizing some of the current theories on the cause of PD, however, it is necessary to describe some clinical observations of patients. Symptoms of PD include "tremors," rigidity, bradikinesia (slowness of movement) and loss of postural control (1). It has been found that patients who show these symptoms for PD have an eighty percent reduction in the levels of both dopamine (a neurotransmitter in the Substantia Nigra) and dopaminergic neurons (neurons that contain dopamine receptors) (1). There are currently four main theories on the cause of Parkinson's Disease: (a) Oxidation of molecules such as iron in the Substantia Nigra by free radicals kill the dopaminergic neurons (1); (b) environmental toxins similar to MPTP (a compound related to the painkiller Demerol), which have been shown to cause Parkinsonism-like symptoms, kill the neurons (1,2); (c) a mysteriously increased rate of dopaminergic neuronal apoptosis in some individuals (1); and (d) Genetic influence, as the penetrance of PD has been observed at higher levels within some families (1). There is evidence for all of these theories, although the most concrete evidence comes from a study that showed increased levels of iron in the Substantia Nigra in PD patients (1). While this study proved nothing, it provided further evidence for a powerful oxidizing agent, such as a free radical, involved in the degeneration of dopaminergic neurons.