Intracellular accumulations and pathologic calcifications L5 Flashcards
what are sub cellular alterations ?
alterations in cells that cannot be seen through a microscope
what are intracellular accumulations ?
accumulations in abnormal amounts that take place within the cell
what are pathologic calcifications ?
deposition of calcium in areas of cell death or normal tissue.
what are the 3 groups of accumulations ?
- )accumulations of constituents of normal cell metabolism produced in excess ex: excess in lipids.
- )accumulation of abnormal substances produced as a result of abnormal metabolism ,
- )accumulation of pigments
what can be accumulated within the cell?
proteins , lipids , and carbohydrates
where exactly can these intracellular accumulations occur?
cytoplasm of nucleus
give an example of accumulation of lipids in the body .
free fatty acids in the liver
ex: obesity and diabetes
how do normal macrophages change to foamy macrophages ?
when they start ingesting excess fat or cholesterol in an attempt to rid the body from these accumulations but fails , the lipid molecules store themselves in the form of lipid vacuoles in the macrophages
when does accumulation of protein occur?
excessive reabsorption of protein in kidneys
when does accumulation of glycogen occur?
when glycogen cannot turn itself into glucose and when the cells capacity to carry glucose is reduced
ex: diabetes
what are some endogenous pigmentations ?
melanin
hemosiderin
lipofuscin
what cells produce melanin ?
melanocytes which are present in the basal cell layer of the epithelium
is melanin a hemoglobin derived pigment ?
no
what enzyme converts tyrosine to melanin ?
tyrosinase
what is oral melanosis ?
excessive melanin deposition due to hyperactivity of melanocytes
what is hemosiderin ?
iron containing pigment derived from the breakdown of hemoglobin .
hemoglobin normally breaks down and when there is breaking down of hemoglobin molecule accompanied by disturbances in iron metabolism . this produces granular or crystalline yellow brown pigment
hemosidren is often seen in macrophages in areas of recent hemorrhage
ex: anemia , excessive dietry intake of iron
..
what are the 2 types of pathological calcification
dystrophic and metastatic calcifications
what is dystrophic calcification ?
calcium salts are deposited in areas of dead or dying tissue with normal serum calcium levels
it is usually seen in areas of necrosis
what is metastatic calcification ?
occurs in normal , viable tissue in the setting of hypercalcemia
increased calcium levels
Vitamin D related disorder
