Zusammenfassung der Ressource
Cell Adaptation and Injury Mindmap
- ATROPHY
Anmerkungen:
- -Decrease in cell size
-Number of cells doesn't change
- Disuse atrophy
Anmerkungen:
- -Decreased energy requirement
-Cell structure changes: Muscles have less ER, mitochondria, filament
- Denervation atrophy
Anmerkungen:
- -Nerve stimulation to muscle lost
-Ex: Stroke patient
- Lack of hormone stimulation
- Inadequate nutrition
- Ischemia
Anmerkungen:
- -Decreased blood flow to organ
-Leads to atrophy of cells and organ itself
- HYPERTROPHY
Anmerkungen:
- -Increase in cell size --> tissue --> organ
-Occurs in cells that can't increase in numbers (Ex: cardiac and striated
-Increased protein, myofilaments, mito
- Physiologic
Anmerkungen:
- -Ex: athletes
-proportional increase in width and length of muscle cell
-Changes stimulated by stretch of muscle fibers
-Promoted by biochemical signals (growth hormone and other ligands --> protein production)
- Pathophysiologic
Anmerkungen:
- -Ex: Heart failure
-Cells not proportional, malformed, not functioning properly
-Change due to different signal molecules
- HYPERPLASIA
Anmerkungen:
- -Increase in number of cells in tissue/organ
-Occurs in cells that can undergo mitosis
-Mechanism: activation of genes controlling cell proliferation
-Increased rate of cell division
- Physiologyic
Anmerkungen:
- -Compensatory response, leads to regeneration and healing
-
- Compensatory hyperplasia
- Hormonal hyperplasia
- Pathologic
- METAPLASIA
Anmerkungen:
- -One cell type is replaced by another that is better able to survive
-Mechanism: undifferentiated cells reprogrammed
-Ex: In smokers, bronchial epithelial cells replaced by squamous cell
- DYSPLASIA
Anmerkungen:
- -Abnormal change in size, shape and organization of cells
-Not a true adaptive change
-Associated with irritation and inflammation
- Stressors
- Excessive
use
- Chemical exposure
- Hypoxia
- Physical Trauma
- Infection and immune reactions
- Genetic chagnes
- Nutritional Imbalance
- Cell Injury
Anmerkungen:
- -Cell membrane, unable to maintain homeostasis
- Causes
- IC Accumulation of substances
Anmerkungen:
- -Cell tries to dispose if they could
-Accumulates in cytoplasm or organelles
- Causes
- Excessive
Anmerkungen:
- Too much normal body substance
Ex: fat in liver (alcoholic cirrosis)
- Abnormal endogenous substance
Anmerkungen:
- Abnormal lipids in brain (Tay Sachs disease)
- Exogenous substance
Anmerkungen:
- From environment
Ex: Coal dust in miner lungs
- Tissue calcification
- Dystrophic
Anmerkungen:
- Ca salts deposited in injured tissues
Ex: Atherosclerosis plaques (contains ca)
Ex: Tuberculosis lesions, includes calcified granulomas
- Metastatic
Anmerkungen:
- Hypercalcemia- deposits to normal tissues
-Also leads to renal calculi (kidney stones)
- Physical agents
Anmerkungen:
- Mechanical trauma
Anmerkungen:
- Temp extremes
Anmerkungen:
- Damage to cells, organelle and enzymes
-Hypothermia and frostbite
- Electrical injury
Anmerkungen:
- damages tissues, disrupts cardiac and nerve impulses
- Radiation
Anmerkungen:
- -Interrupt cell replication, cause mutation, kill cells
-Cause cancers like leukemia
- Chemical exposure
Anmerkungen:
- Mechanisms: injure cell membranes, chemicals block enzyme pathways, coagulate proteins, toxic to cells (ex: liver cells)
- Drugs
Anmerkungen:
- Ex: Acetominophen toxic to liver
- Lead
Anmerkungen:
- Interferes with nerve and brain development
-May be toxic to children
- Mercury
Anmerkungen:
- Toxic to nerves and kidneys
- Infections
Anmerkungen:
- Biologic agents invade and destroy cells
-Viruses change cell DNA
-Bacteria produce toxins
-Microorganisms cause inflammatory/immune response
- Mechanisms
Anmerkungen:
- -Lead to anaerobic metabolism, cell swelling and direct injury to cells
- Free Radicals
Anmerkungen:
- Molecules with unpaired electrons
-Unstable/reactive
-Damage cell membranes, DNA, tissues
- ROS
Anmerkungen:
- Reactive oxygen species
-Oxygen-containing molecules that include free radicals
-Produced by normal process (Ex: metabolic burst accompanying phagocytosis)
- Oxidative stress
Anmerkungen:
- -Occurs when body unable to eliminate ROS
-Plays role in aging and development of disease (Ex: cancer)
- Hypoxic Cell Injury
Anmerkungen:
- Lack of oxygen, interrupts oxidative metabolism, generation of ATP
-Heart, brain and kidneys cells damaged quickly
- Hypoxia
Anmerkungen:
- Lack of sufficient O2 to body cells, tissues and organs
- Causes
Anmerkungen:
- -Blocked blood vessels
-Respiratory disease, blocks inhalation and diffusion of oxygen across alveolar membrane
- Blocked blood vessels
- Respiratory disease
- Loss of hemoglobin
Anmerkungen:
- Carries oxygen to cells
Leads to anemia
- Tissue edema
Anmerkungen:
- Can block oxygen from getting to cells
- Inability to use oxygen
Anmerkungen:
- Ex: lactic acidosis
-Cells unable to use oxygen even though it's being delivered to them
- Results
Anmerkungen:
- Decreased ATP production, cells swell
-Na/K pump fails
-Na and water move into clls
-Vacuoles form
-Cytoplasm swells
-Cells degenerate and rupture
- Call membrane damange
Anmerkungen:
- -Cell destruction releases markers
>Troponin from damaged heart cells
>AST/ALT from damaged liver cells
- Hypoxemia
Anmerkungen:
- Lack of O2 in the blood specifically
- Ischemia
Anmerkungen:
- Lack of enough oxygen to cells or organ
-Leads to anaerobic metabolism
-Ex: Myocardial eschemia- coronary arteries blocked
- Reperfusion Injury
Anmerkungen:
- -Occurs when O2 restored to ischemic tissue
-Ischemia causes increase in ATP consumption, production of xanthine dehydrogenase
-O2 --> metabolizes xanthine to produce massive amounts of superoxide hperoxide
-Radicals cause membrane damage, ca overload of mitochondria
-Mito pores open, ATP escapes, cells die
- Free Radicals
Anmerkungen:
- -Product of xanthine dehydrogenase metabolism from influx of O2 during reperfusion injury
- Anoxia
Anmerkungen:
- Lack of oxygen to cells
Ex: brain - cerebral anoxia
- Impaired Ca homeostasis
Anmerkungen:
- -Ca/Mg pump uses ATP to move Ca out of cell (only precise small amount needed in cell)
-Cell membrane damage allows Ca to enter cell
-Activates enzymes (proteases, lipases, protein kinases) that damage cell membranes, cytoskeleton, proteins, chromatin
*-ases are enzymes that breakdown
- Outcomes
- Recovery
- Apoptosis
Anmerkungen:
- -Programmed cell death
-Purpose: removed injured cells
-Cell fragments engulfed by phagocytes
- Execution Pathways
Anmerkungen:
- carried out by proteolytic enzymes called caspases
- Extrinsic Pathway
Anmerkungen:
- Intrinsic Pathway
Anmerkungen:
- Activated by signals like ROS
- ROS
Anmerkungen:
- Activates intrinsic pathway, which signals apoptosis
- Cell Death
Anmerkungen:
- -Cell death to organ or tissue
-Loss of cell membrane activity and enzyme breakdown of cell parts
- Liquefaction necrosis
- Coagulation necrosis
- Gangrene
Anmerkungen:
- Dry
Anmerkungen:
- Area shrinks, wrinkles
-Turns black
- Wet
Anmerkungen:
- Cell aging theories
Anmerkungen:
- -Molecular: Mutation or changes in gene expression
-Cellular: senescence involving free radical injury, telomere shortening (happens with every cell division), apoptosis
-Decline in integrative functions of organ systems
*Senescence- decline of functioning with age