Topic 3: Degeneration & Necrosis

• adapt

• die

2 things that happens to a cell after injury

degeneration

cell adaptation; implies sick cell

• adapt

• die

2 things that happens to a cell after injury

degeneration

cell adaptation; implies sick cell

necrosis

death of cell, tissue or limited portion of the body

• ER swelling

• Mitochondrial swelling

• small densities

• aggregation of intramembranous particles

• bleb formation

• generalized swelling

• dispersion of ribosomes

• clumping of nuclear chromatin

• autophagy of lysosome

hallmarks of degeneration (9)

• defects in cell membrane

• myelin bodies

• ER lysis

• mitochondrial swelling & rupture

• large densities

• rupture of lysosome & autolysis

• nuclear pyknosis, karyorrhexis, or karyolysis

hallmarks of necrosis (7)

pyknosis

condensation of nucleus

karyorrhexis

nucleus fragmentation

karyolysis

dissolution of nucleus

• cell swelling

• ballooning degeneration

• hydrophobic degeneration/serous infiltration

• hyaline degeneration

• mucoid degeneration

• fatty degeneration

• fibrinoid degeneration

• colloidal degeneration

• wallerian degeneration

forms of degeneration (9)

cell (cloudy) swelling

accumulation of fluid in cytoplasm

ballooning degeneration

accumulation of fluid in cytoplasm of epidermal cells

hydrophobic degeneration/serous infiltration

more advanced cell swelling; cell has tendency to burst

hyaline degeneration

formation & accumulation of hyaline in tissue

mucoid degeneration

formation & accumulation of mucin granules

fatty degeneration

deposition of fat globules

fibrinoid degeneration

deposition/replacement of eosinophilic granular/globular subs. resembling fibrin

colloidal degeneration

conversion of tissue into gelatinous or gum-like material

wallerian degeneration

degeneration of nerve fiber and its myelin sheath

• coagulative

• caseation

• liquefactive

• gangrenous

• fat

• infarct

• Zenker’s

forms of necrosis (7)

coagulative

cells are deac but tissue architecture is still intact and maintain a solid consistency

caseation

cells are dead and tissue architecture is lost and appears cheesy

liquefactive

there is complete dissolution of tissue and tissue undergoes self-digestion

gangrene

product of necrosis plus bacterial putrefaction

dry gangrene

originates fro coagulative necrosis

wet gangrene

originates from liquefactive necrosis

fat necrosis

due to reaction of lipase on adipose, resulting to saponification

infarct

area of coagulative necrosis in tissue due to sudden stoppage of blood flow through artery or vein

Zenker’s necrosis

degeneration and necrosis of striated muscle