PSYC 211 Lecture Notes - Lecture 52: Frontotemporal Dementia, Striatum, Amyloid
Document Summary
Tse is caused by proteins called prions (protein infectious agents) Healthy prions (prpc) are found in membranes where they play a role in synaptic function. The infectious protein (prpsc) is identical to the healthy protein. Prpc and prpsc differ in their 3d shape; the difference is in the way the protein is folded. Once the mis-folded prpsc is introduced into the cell, it causes healthy prpc to mis-fold aswell. Prpsc"s are resistant to proteolytic enzymes and heat. Parkinson"s disease (pd) is caused by degeneration of the nigrostriatal system. Surviving dopaminergic neurons show lewy bodies: abnormal circular structures in the cytoplasm. Pd is associated with a mutation of a gene located on chromosome 4. The gene normally produces -synuclein which is involved in synaptic transmission in dopaminergic neurons. Abnormal accumulation of -synuclein is toxic to the cell and causes aggregations in dopaminergic neurons. L-dopa replenishes the brain of its lost dopamine.