| Acetylcholinesterase | An enzyme that helps degrade the nerve transmitter substance “acetylcholine”. Acetylcholinesterase is normally found at the point at which two nerves communicate. |
| Amyloid | An abnormal substance deposited between and within cells. Amyloid stains with the Congo Red stain. In Alzheimer’s disease amyloid is abnormally deposited in neuritic plaques and in small blood vessels. |
| APP | Amyloid Precursor Protein (APP) is a protein of uncertain function that is normally found in the brain. In Alzheimer’s disease, APP is abnormally degraded resulting in the formation of amyloid. |
| Knock-out mice | An experimental strain of mice that has been genetically engineered in the laboratory such that a specific gene is deleted from the DNA of the mouse. Knock-out mice are extremely useful tools that scientists use to study the function of the gene that has been “knocked-out” of the DNA. |
| Mutation | An abnormal permanent change in the DNA sequence. Mutations can be thought of as “typographical errors” in the DNA code. |
| Neuritic plaques | Abnormal collections of nerve processes surrounding a central core of amyloid. Neuritic plaques, together with neurofibrillary tangles, are the hallmarks of Alzheimer’s disease. |
| Neurodegenerative | An abnormal deterioration of the nervous system. |
| Neurofibrillary tangles | Abnormal bundles of filaments in nerve cells in the brain. These filaments contact on protein tau and are of the typical features of Alzheimer’s disease. |
| NSAIDs | Non-steroidal anti-inflammatory drugs. |
| PS1 | Presenilin-1 (PS1) is a protein produced in brain cells. Inherited mutations of the PS1 gene on chromosome 14 are a cause of Familial Alzheimer’s Disease. |
| PS2 | Presenilin-2 (PS2) |
| Secretase | A group of enzymes found in brain cells (alpha-secretase, beta-secretase, and gamma-secretase. The secretases function to degrade APP. The abnormal degradation of APP can result in the accumulation of amyloid in the brain and the development of Alzheimer’s disease. |
| Transgenic mice | An experimental strain of mice that has been genetically engineered in the laboratory such that a specific gene is added to the DNA of the mouse. Transgenic mice are an invaluable resource for scientists who wish to study the function of a specific gene |
