Intro to Pathology Flashcards
general mechanisms of cell injury
-disruption of metabolism
-inflammatory processes
-infectious diseases
-diseases of immunity
-environmental injury
-neoplasia
-genetic disorders
adaptations as a cellular response are reversible, and include:
-atrophy
-hypertrophy
-hyperplasia
-metaplasia
hypertrophy
increased size of an organ/tissue caused by an increase in SIZE of cells
pathogenesis of hypertrophy
increased synthesis of cellular components → increase in cell SIZE
example of physiologic hypertrophy
uterus enlarging during pregnancy
example of pathologic hypertrophy
*left ventricular hypertrophy and cardiomyopathy
(clinical correlation: compromises cardiac function)
hyperplasia
increased size of an organ/tissue caused by an increased NUMBER of cells
pathogenesis of hyperplasia
increased mitotic activity/cell division → increased NUMBER of cells
example of physiologic hyperplasia
female breast exhibits hyperplasia during lactation for increased functional capacity
example 2 of physiologic hyperplasia
compensatory hyperplasia of the liver as a result of liver damage (increased mass following damage or loss)
examples of pathologic hyperplasia
-benign prostatic hyperplasia
-endometrial hyperplasia
-gynecomastia (breast growth in males)
-verruca plantaris (plantar warts)
dysplasia
disordered hyperplasia (can result from pathologic hyperplasia or metaplasia and can turn into neoplasia)
atrophy
decreased size of an organ/tissue caused by a decrease in mass of cells (size and/or number)
pathogenesis of atrophy
- reduction of cellular components
- loss of cells (apoptosis)
example of pathologic atrophy
alzheimers (results in loss of parenchyma)
cachexia (loss of adipose)
atrophic gastritis (antibodies attacking cells that make intrinsic factor - parietal cells)
metaplasia
replacement of one differentiated tissue by another (reprogramming of a cell to make a diff type of cell)
pathogenesis of metaplasia
*reprogrammed stem cells (persistent influences leading to metaplasia may induce neoplasia)
*usually due to exposure to an irritant (gastric acid, tobacco smoke, etc)
example of pathologic metaplasia
Barrett’s esophagus (making goblet cells in esophagus to protect from chronic acid reflux)
principles of cell injury
- injury depends on cause (duration, dose, type)
- injury depends on the cell’s specific response (cells respond differently to different things)
- injury results from functional abnormalities in one or more interconnected cellular components
top etiologies of cell injury
- oxygen deprivation (hypoxia or ischemia)
- chemicals
roles/functions of mitochondria in cell injury
decreased ATP production, high conductance channels, and leakage of cytochrome c into cytoplasm
roles/functions of ATP depletion in cell injury
- reduced plasma membrane energy-dependent pumps (loss of Na+/K+ ATPase leads to cell swelling and ER dilation)
- altered cell metabolism (reliance on glycolysis and increased lactic acid)
- reduced protein synthesis
- unfolded protein responses
- mitochondrial membrane damage
roles/functions of calcium in cell injury
*important mediator of cell injury (cell injury leads to influx of calcium)
*increased calcium in the cell causes enzymes to function, even when they shouldn’t be on
roles/functions of free radicals in cell injury
molecules with unpaired electrons that, pathologically, disrupt macromolecules