Dictionary > Neurofibrillary tangles

Neurofibrillary tangles

neurofibrillary tangles
abnormal structures located in various parts of the brain and composed of dense arrays of paired helical filaments (neurofilaments and microtubules). These double helical stacks of transverse subunits are twisted into left-handed ribbon-like filaments that likely incorporate the following proteins: 1) the intermediate filaments: medium– and highmolecularweight neurofilaments; 2) the microtubule-associated proteins map-2 and tau; 3) actin; and 4) ubiquitin. As one of the hallmarks of alzheimer disease, the neurofibrillary tangles eventually occupy the whole of the cytoplasm in certain classes of cell in the neocortex, hippocampus, brainstem, and diencephalon. The number of these tangles, as seen in post mortem histology, correlates with the degree of dementia during life. Some studies suggest that tangle antigens leak into the systemic circulation both in the course of normal aging and in cases of alzheimer disease.

You will also like...

The process of photosynthesis
Photosynthesis – Photolysis and Carbon Fixation

Photosynthesis is the process that plants undertake to create organic materials from carbon dioxide and water, with the ..

Freshwater aquatic plankton
Freshwater Communities & Plankton

Planktons are microscopic organisms that live suspended in aquatic habitats. There are two groups: the phytoplanktons an..

An artist's depiction of the origin of amphibians
Amphibians & Early Reptiles

Obtaining air outside an aquatic environment required species to acquire suitable adaptations, and this was the case of ..

Early Earth
The Origins of Life

This tutorial digs into the past to investigate the origins of life. The section is split into geological periods in the..

An artist depiction of a Precambrian multicellular life form.
The Evolution of Cell Organelles

The nucleus containing the genetic material, DNA, and the mitochondria, well-identified as the "powerhouse of the cell",..

Neural Control Mechanisms
Neural Control Mechanisms

Neurons generate electric signals that they pass along to the other neurons or target tissues. In this tutorial, you wil..