Intracellular & Extracellular accumulation

What are the 4 intracellular accumulations

Defect in metabolism, defect in protein folding/transport, Lack of inherited enzyme deficiencies, ingestion/inhalation of indigestible materials

What is defect in metabolism

Fatty change such as lipidosis/steatosis in the liver

What is defect in protein folding/transport

Accumulations can occur secondary to misfolded proteins or from an inability to transport proteins out of the cell

What does Lack of enzyme do

Failure to degrade a substrate due to inherited enzyme deficiencies

what is the mechanism of Ingestion/ inhalation of indigestible materials

accumulation of carbon

Intracellular accumulations: lipid is what?

Abnormal accumulation of triglycerides

causes include toxins, protein malnutrition, diabetes, obesity,decreased perfusion

What are the mechanisms of lipidosis/steatosis

Negative energy balance, decreased oxidation of FFA, decreased apoprotein synthesis, decreased/ineffective lipoprotein synthesis, ineffective lipoprotein transport outside the cell

Atherosclerosis

cholesterol accumulation in arteries, in smooth muscle and subintimal space of medium to large arteries, appear as clear lipid/ foamy macrophages

Intracellular accumulation: Glycogen

Source of stored energy in cell appears as clear vacuoles

Pigment Accumulation Red

Heme part of hemoglobin from vasodilation, hemorrhage, or hemoglobin imbibition

Pigment Accumulations: Green

Old hemorrhage(biliverdin) & eosinophilic infiltrate

Seen in birds chromic hemorrhage

Pigment accumulation: Brown

Pathologic and non-pathologic

Hemosiderin, ceroid-lipofuscin, melanin

Hemosiderin

A hemoglobin break down product which discolors affected organs brown

Lipofuscin

Brown

Wear and tear pigment

Indicator of oxidative damage, age of cell

Ceroid

Pathological brown pigment

Indicator of oxidative injury

Nutritional panniculitis

Vit E deficiency

Pigment accumulation: Yellow

Bilirubin

End of product of hemoglobin metabolism

Produced within liver pre-hepatic, hepatic, post-hepatic

What are Carotenoids

Exogenous from diet, horses& some cattle breeds from leafy green plants

Product of erythrocyte breakdown

Heme—>biliverdin—>bilirubin—>conjugation in liver—>urobilinogen in GIT

Causes of hyperbilirubinemia/icterus

Prehepatic(hemolysis), Hepatic (liver dz), Post-hepatic (obstruction of bile)

Pigment accumulation: Black Melanin

Black brown pigment produced by melanocytes

ONLY endogenous black brown pigment

Non pathologic: skin, retina, meninges

Pathologic: melanocytic neoplasm, hyperpigmentation in skin

Amyloidosis

Protein-folding disorder resulting in deposition of misfolded insoluble protein (amyloid) between cells, causing tissue distortion and dysfunction

Extracellular

Local or systemic

Sharpei and Siamese cats=hereditary

Morphology of amyloid

Where is it found

Enlarged waxy pale dark brown

Liver,spleen,kidney

Intra/extra cellular accumulation: Mineral

What are the two forms

Deposition of calcium salts in tissue not normally mineralized

Dystropic-localized mineral deposition in areas of tissue injury and/or necrosis. Intracell=mitochondria Extracell=membrane bound matrix vesicles

Metastatic= result of ststemic Ca:P imbalance