Ch2 Growth Alterations EC Flashcards
Causes of atrophy
Decreased hormone stimulation (ie. hypopituitarism)
Decreased innervation (ie ALS)
Decreased blood flow (ie cerebral atrophy in atherosclerosis)
Decreased nutrients (ie marasmus)
Compression atrophy
Increased luminal pressure
(ie hydronephrosis)
(ie pancreas in CF)
Autophagy
Enzyme degradation of organelles
Vacuoles with organelles fuse with lysosomes
Brown atrophy
Increased lipofuscin in cells (undigested lipid)
Three mechanisms of atrophy
Autophagy
Apoptosis
Decreased protein synthesis/Increased protein degradation
Remaining kidney postnephrectomy
Undergoes compensatory hypertrophy
CMV hypertrophy of cell
Increase Fe uptake causing increased cell growth
Five causes of hyperplasia
Increased hormone stimulation (ie endometrial hyperplasia) Chronic irritation (bronchial mucus glands in smokers) Chemical imbalance (hypocalcemia-parathyroid hypertrophy) Stimulating antibodies (Grave's disease) Viral infections (HPV)
Labile cells
Continuously divide (bone marrow stem cells)
Stable cells
Resting in G0, can re-enter cell cycle if stimulated
hepatocytes, astrocytes, SM cells
Permanent cells
Cannot divide
neurons, skeletal/cardiac muscle
Squamous to glandular epithelium
Metaplasia due to acid reflux in distal esophagus (Barrett’s)
Presence of Paneth cells in stomach
Metaplasia due to H. pylori
Glandular to squamous epithelium
Bronchus in smokers
Endocervix
Transitional to squamous epithelium
Schistosoma haematobium infection of urinary bladder