Basics-Celldeath Flashcards
What is Apoptosis and what does the Cell must have to get into Apoptosis?
- Apoptosis is programmed cell death
- The cell needs ATP to put Apoptosis to practice
What pathways does Apoptosis has?
What is the common general mechanism of both pathways?
Intrinsic and extrinsic pathways
-> both pathways lead to activation of cytosolic caspases
(zytosolischen Caspasen)
How big is the inflammation, when Tissue getsinto Apoptosis?
No significant inflammation
When does the intrinsic pathway occure?
Involved in tissue remodeling in embryogenesis
(Bei der Embryogenese ist die Apoptose in allen Geweben nachweisbar)
Occures when a growth factor is withdrawn (abgezogen, weg)
from a proliferating cell population
-> Example: IL-2 is withdrawn after a completed immune reaction
This results -> Apoptosis of proliferating effector
cells
Also occurs after exposure to injurious stimuli
like radiation, toxins, hypoxia
What are the biochemical events, which characterize the intrinsic pathway of Apoptosis?
The Change of proportion (Verhältnis) of anti-apoptotic (Bcl-2) and
pro-apoptotic (Bax) factors
-> this leads to increased mitochondria permeability and
cytochrom C release
(This Cytochrome C activates the cytosolic caspases and leads to
cellular breakdown)
Discribe the Extrinsic pathway of Apoptosis!
2 pathways:
- Ligand receptor interactions (Fas ligand binding to Fas-R(CD95))
- Immune cell(cytotoxic T-cell release of perforin and granzyme B)
-> these both ways are activating the cytosolic capsases which
leads to cellular breakdown
What leads to necorsis.
Enzymatic degradation (Zersetzung, Abbau) and Protein denaturation of a cell resulting from exogenous injury
Does Necrosis has inflammatory components?
Yes there is inflammatory process (unlike apoptosis)
There is also intracellular components extravasate (Flüssigkeit welche Ödeme bildet)
What type of Necrosis do we Have:
- Heart, liver, kidney
- brian, bacterial abscess, pleural effusion
- Tuberculose, systemic fungi
- peripancreatic fat (saponification=Verseifung via lipase)
- blood vessels
- dry (ischemic coagulative) or wet (with bacteria); common limbs
and GI tract
What type of Necrosis do we Have:
- Coagulative (koagulations) - Heart, liver, kidney
- Liquefactive (colliquative necrosis) - brian, bacterial abscess,
pleural effusion - Caseous (Verkäsung) - Tuberculose, systemic fungi
- Fatty (verfettend) - peripancreatic fat (saponification=Verseifung
via lipase) - Fibrinoid - blood vessels
- Gangrenous - dry (ischemic coagulative) or wet (with bacteria);
common limbs
and GI tract
Was versteht man unter Nekrose?
Eine intravital auftretende morphologische Veränderung einer Zelle nach ihrem Absterben
So geht die Nekrose üblicherweise andere - reversible - Veränderungen Voraus (Schwellung, Verfettung)
Nenne fünf wichtige Grundbereiche, in welcher Apoptose aktiv ist!
- Während der Embryogenese
- Bei der Gewebserneuerung (z.B nach Sonnenbrand
- Bei der Zellerneuerung wie bei Blutzellen
- Bei Tumorgewebe
- Während der Zytostatika Behandlung
Wie sehen Zellen mit Apoptose aus?
- Verklumptes Chromatin entlang der Kernmembran
- Der Kern schrumpft (Karyopyknose)
- Zelle Schrumpft durch Wasser Verlust
- Beim Zerfall der Zelle entstehen Fragmente die
Apoptose-Körperchen heißen
Was gibt es bei der Apoptose nicht, was es bei der Nekrose gibt?
Eine Entzündungsreaktion fehlt bei der Apoptose
Wie ist eine Nekrose Initial gekennzeichnet?
Nekrose:
Initiale hydropische Zellschwellung
What happens with the Nucleus during the Necrosis?
Pyknosis (schrumpfender Kern) -> Karyorrhexis -> Karyolysis
