General Pathology – Seminar 2
Necrosis
Atrophy causes
Jaroslava Dušková
Inst. Pathol. ,1st Med. Faculty, Charles Univ. Prague
http://www1.lf1.cuni.cz/~jdusk/
Death
irreversible damage of the
morphological & functional
integrity of
cells
organism
Cell Death
apoptosis
 necrosis

Apoptosis
induced (from outside) or
 genetically programmed cell

death
(cell execution / suicide)
logical and functional contrary to mitosis
 a system for the removal of unnecessary,
aged, or damaged cells

Apoptosis -1
• Triggered by a wide range of stimuli.
• Cell surface receptors like Fas or
tumor necrosis factor receptor 1 (TNFR1).
• Interplay of proapoptotic (Bax, Bad, Bid, Bik,
and Bim) and antiapoptotic (Bcl-2 and Bcl-XL)
proteins
Apoptosis
Morphology
– chromatin condensation
– cell shrinkage
– budding and forming of apoptotic bodies
(emission of pseudopodia)
– karyorrhexis
(not pathognomonic for apoptosis)
Apoptosis
Meaning
physiological process
necessary for right organ
formatting and life course
 pathological process leading to
organism damage - e.g. atrophy

Apoptosis
Ontogenesis
intestinal mucose, genit. tract,
immune system - T lymphocytes
Regeneration of tissues and organs
intestinal mucose, blood
Physiological involution
Atrophy
neonatal adrenal cortex, thymus,
breast after lactation period
preassure, hyperplasia regression,
slight ischemia
Necrosis
cell death caused from
external insult
Necrosis
Biochemistry
– no expression of genes de novo
– energy dependent membrane
systems damaged
hypoxia, toxins
– changes in concentrations of ions
– increased water volume (oncosis)
– autolysis
Necrosis
Morphology
– pyknosis, karyorhexis, karyolysis
– denaturation of proteins - eosinophilia
– cell swelling
– cell budding
(cytoplasmic protrusions)
Necrosis
Meaning
pathological process
leading to a temporary
organism damage or death
Necrosis
Classification
according to the tissue macroscopy:
–
–
–
simple
liquefaction
coagulation
+ special types: caseation,
Zenker´s of waxy appearance
Necrosis –
–
–
further development:
no
death of organism
gangrene
sicca (dry g.)
humida (wet g.)
emphysematosa (gas g.)
demarcation, sequestration
regeneration
repair
Necrosis

- Causes:
chemical
– chlorinated hydrocarbons, heavy metal
compounds, ethyl- alcohol, aphlatoxins, ...

physical
– mechanical trauma, UV light, ionizing
radiation, heat, cold, ….

biologic
– bacteria, viruses, fungi...
Atrophy
diminution of organ or tissue
after full development has
been attained
(versus hypoplasia, aplasia)


simple
numerical
(x hypertrophy)
(x hyperplasia)
Atrophy - causes:

vascular
pressure
inactivity
inanition
neurogenic

ionizing radiation









involution
senile
postinflammatory
endocrine
unknown cause
Atrophy - meaning:


may be reversible
loss of specialised structures
& hypofunction
clinically silent or unimportant
(involution)
 clinically apparent


metaplasia, increase of the supportive
tissues - pseudohypertrophy