Week 2 25/01/21-29/01/21 Flashcards
What does hypertrophy of cells mean?
↑ed cell size, ==> ↑ organ size
↑ed production of cellular proteins
Hypertrophied organ X new cells, just larger cells
Synthesis of more structural components of cell
What three factors can induce hypertrophy of cells?
Mechanical sensors, triggered by ↑ed work load
Growth factors incl: TGF-β, IGF-1, fibroblast growth factor
Vasoactive agents e.g. α-adrenergic agonists,
endothelin-1, angiotensin II
What is hyperplasia of the cells?
↑ cell no in organ/tissue ==> ↑ed mass of organ/tissue
Occurs if cell pop is capable of dividing
What are the two types of physiological hyperplasia?
Hormonal hyperplasia, ↑ functional capacity of a tissue when needed
Compensatory hyperplasia, ↑ tissue mass after damage/partial resection
What is the cause of pathological hyperplasia?
Excesses of hormones/growth factors acting on target cells
What is cellular atrophy?
↓ed organ/tissue size resulting from ↓in cell size + no
What are the different types of atrophy?
↓ed workload (atrophy of disuse)
Loss of innervation (denervation atrophy)
Diminished blood supply (senile atrophy)
Inadequate nutrition (marasmus, cachexia)
Loss of endocrine stimulation (endometrium, breast)
Pressure (tissue compression)
What are the mechanisms of atrophy?
↓ed protein synthesis + ↑ed protein degradation in
cells cos of reduced metabolic activity
What is metaplasia of cells?
Reversible change, one differentiated cell type (epithelial/mesenchymal) replaced by another cell type
What is cell necrosis?
Morphological changes that follow cell death in a LIVING tissue/organ, largely resulting from progressive, degradative action of enzymes on lethally injured cell
What are 2 causes of cell necrosis? (Types of enzymes)
Cell’s own degradative enzymes = Autolysis
Enzymes released by white cells + complement = Heterolysis
What is apoptosis of cell?
Chromatin condensation + DNA fragmentation
e.g. deletion of cells in: normal development, organogenesis, immune function, tissue growth
What are the 4 types of necrosis?
Coagulative necrosis e.g. MI/ paracetamol overdose in liver
Liquefactive necrosis e.g. cerebral infarct/abscess
Caseous necrosis e.g. tuberculosis
Fat necrosis e.g. in acute pancreatitis
What is gangrene?
Necrosis + putrefaction (i.e. rotting)
What are the 3 main types of diuretics? What are they used for?
Oedematous conditions - loop diuretics, K+ sparing diuretics
Hypertension - thiazide type diuretics
How do hydrostatic and osmotic pressures work in microvasculature? (kidneys)
Hydrostatic - pushes H2O out
Osmotic - pushes water in
Where do the different diuretics act on?
Loop diuretics - ascending loop of Henle
Thiazide diuretics - DCT
K+ sparing diuretics - collecting ducts
What drugs are loop diuretics?
Furosemide, Torsemide
What conditions are loop diuretics used for?
Oedematous conditions e.g. heart failure. hepatic cirrhosis, glomerulonephritis
What are potential adverse affects of loop diuretics?
Hypokalaemia, Metabolic acidosis Depletion of plasma Ca2+, Mg 2+ Ototoxicity (deafness, uncommon) Hypovolaemia
What drugs are thiazide type diuretics?
Bendroflumethiazide, Indapamide
Metolazone (thiazide like)
What type of diuretics should be used to treat hypertension? How much?
Low doses of thiazide-like drugs
What are the adverse effects of thiazides?
Hypokalaemia
Hyperglycaemia
Hyperuricaemia
Metabolic alkalosis
