092614 path of atherosclerosis Flashcards
(34 cards)
examples of large or elastic blood vessels
aorta and major branches (innominate, subclavian, common carotid, iliac) and pulmonary artery
ex of medium sized or muscular arteries
coronary arteries
renal arteries
small arteries and arterioles are found where?
coursing within connective tissue of organs
diff btwn elastic and muscular arteries w respect to the media
in elastic artery, elastic fibers alternate btwn sm muscle cells in media
in muscular artery, the media has primarily sm musc cells; elastic fibers are limited to internal and external elastic lamina
arterioles’ elastic composition?
arterioles have thin internal elastic membrane
terminal arterioles have no elastica
what does medial sm musc contraction in arterioles cause?
adjustment of blood pres and blood flow
arterioles have thin internal elastic membranes and are points of physiologic resistance
size of capillaries in diameter
7-8 microns
what other cells can capillaries by surrounded by other than endothelium
pericytes (smooth musc like cells)
what are the vessels at which leukocytes emigrate in inflam?
venules
characteristics of veins
large lumen, thin wall
endothelial cells can do what
maintain barrier anticoagulant, antithrombotic, fibrinolytic regulators prothrombotic molecules make ECM modulate blood flow regulate inflam regulate cell growth oxidize LDL
how do endothelial cells respond to injury?
two types of response (in terms of timing):
stimulation–is immediate response. rapid and reversible. independent of new protein synthesis. an example would be contraction of endothelial cells in response to histamine
activation–elaboration of gene products with biologic activity requires hours or days to develop
how can endothelial cells be turned into activated state from its basal state?
by factors like turbulent flow, HTN, lipid products, advance glycation end-products, cigarette smoke, etc
what do endothelial cells in the activated state do?
increase expression of procoagulants, adhesion molecules, proinflammatory factors
alter expression of chemokines, cytokines, growth factors
role of vascular sm musc cells
vasoconstriction or dilation
making collagen, elastin, proteoglycans
elaboration of growth factors and cytokines
migration to intima and proliferation in normal vascular repair and pathologic processes such as atherosclerosis
what are pro-growth factors on the vascular sm muscle cells
PDGF, endothelin, thrombin, FGF, IFN-gamma, IL-1
what do sm musc cells do in response to vascular injury
migrate from media into intima
in intima, will undergo mitosis
then will make ECM
intima, as aresult, thickens
intimal sm musc cells are different from normal sm musc cells how?
they cannot contract
arteriosclerosis
hardening of the arteries
types of arteriosclerosis
atherosclerosis-elastic arteries and large/medium muscular arteries
arteriolosclerosis–small arteries and arterioles
Monckeberg medial calcific sclerosis
Monckeberg arteriosclerosis
calcific depositis in media and internal elastic lamina of MEDIUM sized muscular arteries (usually radial and ulnar arteries)
greater than 50 years of age
no obstruction to blood flow
ring shaped (vs eccentric for an atheroma)
usually not clinically significant
two basic types of damage in atherosclerosis
aneurysm formation
stenosis
morphology of fatty streak
multiple yellow, flat dots to streaks. usually in aorta and later in coronaries
may be a precursor of atheroma but not all fatty streaks develop into more advanced lesions
atheroma
fibrofatty plaque
