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Alzhiemer’s Disease Essay, Research Paper Alzheimer’s Disease Alzheimer’s Disease is a progressive and irrevocable brain disease that destroysmental and physical functioning in humans, and perpetually leads to death. It is thefourth leading cause of adult death in the United States, affecting 2.5 to 3 million peopleeach year. The cause has not yet been identified, nor has a cure been discovered, butresearch advances are being made. To fully be able to understand and fight Alzheimer’s Disease, one must know howit affects brain, the part of the body that it takes the largest toll on. Autopsies on manyAlzheimer’s Disease sufferers show that a large number of differences were presentwhen comparing a normal brain to their’s. There was a loss of nerve cells from

thecerebral cortex in the Alzheimer’s victim: approximately 10% of the neurons in thisregion were lost. Although a 10% loss is relatively minor, and cannot account for thesevere impairment suffered by Alzheimer’s victims. Neurofibrillary tangles are found in the brain within the cell bodies of nerve cellsin the cerebral cortex, and take on the structure of a double helix. Other diseases thathave double helixes include Parkinson’s disease, Down’s Syndrome, and DementiaPugilistica. Scientists are not sure how the double helixes are related in these verydifferent diseases, or if they even are related. Neuritic plaques are patches of clumped material lying outside the bodies ofnerve cells in the brain. They are mainly found in the cerebral cortex, but have also beenseen in

other areas of the brain. At the core of each of these plaques is a substance calledamyloid, an abnormal protein not usually found in the brain. This amyloid core issurrounded by cast off fragments of dead or dying nerve cells. The cell fragmentsinclude dying mitochondria, presynaptic terminals, and double helical filaments identicalto those that are neurofibrillary tangles. Many neuropathologists think that these plaquesare clusters of degenerating nerve cells, but they are still not sure of how and why thesefragments clustered together. Congophilic Angiopathy is the technical name that neuropathologists have given to an abnormality found in the walls of blood vessels in the brains of victims ofAlzheimer’s. These abnormal patches are similar to the neuritic plaques that

develop in Alzheimer’s, in that amyloid has been found within the blood-vessel walls wherever thepatches occur. Another name for these patches is cerebrovascular amyloid, meaning”amyloid found in the blood vessels of the brain.” Acetylcholine is a substance that carries signals from one nerve cell to another. Itis known to be important to learning and memory. In the mid ’70s, scientists found thatthe brain of a person afflicted with Alzheimer’s Disease contained 60% to 90% less of theenzyme choline acetyltransferase (CAT), which is responsible for producingacetylcholine, than did the brain of a healthy person. This was a great milestone in thefight against Alzheimer’s, as it was the first functional change related to learning andmemory, and not to different

structures. Somatostatin is another means by which cells in the brain communicate with eachother. The quantities of this chemical messenger, like those of CAT, are also greatlydecreased in the cerebral cortex and the hippocampus of Alzheimer’s victims, almost tothe same degree as CAT is lost. Although scientists have been able to identify many of these and other changes,they are not yet sure as to how, or why they take place in Alzheimer’s Disease. They areso near to completing the mystery of Alzheimer’s, but yet still so far away. If treatment is required for someone with Alzheimer’s Disease, the Alzheimer’sDisease and Related Disorders Association(ADRDA), should be contacted. It is a privately funded, national, non- profit organization dedicated to finding a cure and