Flashcards in Lecture 10 - Artherosclerosis Deck (13):
Tunica media functions?
regulate flow by contraction, stabilise epithelium by secreting ECM and activating TGF-beta
Elastic Lamina layers function?
assist continuous flow
Most common positive risk factors?
hyperlipidemia (cholesterol), smoking, hypertension, diabetes mellitus, ageing
Negative risk factors?
high levels of circulating high density lipoproteins, moderate alcohol, CV fitness
Response to injury hypothesis - causes?
haemodynamic force, chemical insults, cytokines
Response to injury theory - effects?
altered permeability, adhesion of leukocytes leading to inflammation, thrombosis
Leukocyte migration into developing plaque?
circulating monocyte adherence, entry into lesion, differentiation into macrophage, ingested oxidised lipoproteins turning into foam cells, cytosolic contents enter ECM @ necrosis/apoptosis
Role of smooth muscle cell activation and migration?
macrophages, platelets and EC produce growth factors activating SM, proliferate and migrate into tunica intima (accelerated by failed IEL).
Role of lipoprotein entry and oxidation?
oxidised in plaques, attract monocytes, stimulate several cell types to release cytokines and GF, leading to dysfunction and apoptosis of EC, SM and macrophages
thin fibrous cap, high lipid content of core, inflammation
Occurrences leading to symptoms?
rupture, haemorrhage, thrombosis, tunica media weakness leading to dissection
Common Clinical Consequences?
MI, peripheral vascular disease, CV disease