Causes of Alzheimer's Disease
Synonyms in the broader sense
Alzheimer's disease causes, causes of dementia, Alzheimer's dementia
The Alzheimer's dementia is marked by a downfall of Brain cellswhich is in a shrinkage (atrophy) of the affected brain regions. The cerebral cortex is particularly affected (Cortex) of the frontal, temporal and parietal lobes and the Hippocampus. The hippocampus is a central switching station of the limbic system, which i.a. is responsible for intellectual performance. Later on, the medullary bed with the pathways of the brain cells is also affected. The decrease in the number of synapses is related to clinical symptoms affecting the mind (cognitive), together. However, the clinical symptoms do not necessarily correspond to the extent of the discernible changes.
The is also regularly affected Nucleus basalis Meynert, a core of the central nervous systemthat goes directly to the frontal lobe (frontal cortex) connected is. The connecting pathways contain the messenger substance (Neurotransmitters) Acetylcholine, which in a degeneration of the nucleus basalis Meynert in a reduced concentration in the brain present. In addition, further conduction pathways with the neurotransmitters Norepinephrine and Serotonin that lead to the hippocampus. The lack of the said neurotransmitters may explain part of the symptoms.
Deceased in autopsy specimens of the brains Alzheimer - Under the microscope, patients show increased deposits of certain "protein clumps" (senile plaques) and "threads" (Alzheimer's fibrils), which only develop in the later course of the disease and lead to the loss of function and destruction of Neurons (Neurons) to lead. The fibrils lie in the cells (intracellular) and consist of the protein τ. The plaques are outside the cells (extracellular) found in the hippocampus, cortex and other brain regions. The deposits occur to a much lesser extent as part of the normal aging process or other diseases of the brain, but this is suspected to be a cause of the progressive degradation processes in the brain of those with Alzheimer's disease. The Alzheimer's fibrils and the amyloid plaques are in a certain, but not yet quantitatively determinable amount for Alzheimer's disease characteristic but not specific!