Canadian Medical Guide > Anatomy > Nervous System > Neurons > Neurofibrils Terms and Definitions




Neurofibrils

Medical Definition: The delicate interlacing threads, formed by aggregations of neurofilaments and neurotubules, coursing through the cytoplasm of the body of a neuron and extending from one dendrite into another or into the axon.
Guide Notes: A 11 qualif except /cytol; /genet permitted; do not confuse with NERVE FIBERS
Neurofibrils Categories.
Canadian Medical Guide Definition 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 high-molecular-weight neurofilaments; (2) the microtubule-associated proteins map-2 and tau; (3) actin; and (4) UBIQUITINS. 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, brain stem, 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.

Neurofibrils Medical Definitions and Terms

CANADIAN MEDICAL GUIDE

Thank you for visiting Canadian Medical Guide .com





Wildlife On Video »

Canadian Medical Guide Canada's Great Outdoors
Tour Canadian Rockies »
Book Banff »
Book Jasper »
Maligne Lake Boat Cruise »
Gondola Banff »
Hike Jasper »
Jasper Columbia Icefield »