Week 1 Part 2 Flashcards
What are the three layers of blood vessel?
Vascular intima (inner layer)
Vascular media (middle layer)
Vascular adventitia (outer layer)
provides interface between circulating blood throughout
the body
Vascular intima
its endothelial surface is usually inert to platelets and coagulation (termed as non-thrombogenic surface)
Vascular intima
if the lining is disrupted, the injured vessel and its adjacent vessel constricts (vasoconstriction)
Vascular intima
Tunica intima
the innermost lining of blood vessels is a monolayer of
metabolically active _____________.
Endothelial cells
Anticoagulant Properties of Vascular Intima
Prostacyclin
Nitric Oxide
Tissue Factor Pathway Inhibitor
Thrombomodulin
Heparan sulfate
Platelet inhibitor
Prostacyclin (PGI2)
Vasodilator
Prostacyclin
Synthesized through the eicosanoid pathway
Prostacyclin
Induces smooth muscle relaxation (vasodilation)
Nitric oxide
Inhibits platelet activation
Nitric oxide
Promotes angiogenesis
Nitric oxide
Synthesized in ECs, vascular smooth muscle cells, neutrophils, and macrophages
Nitric oxide
Controls activation of the tissue factor pathway
Tissue Factor Pathway Inhibitor
Limits the activation of the TF:VIIa:Xa complex
Tissue Factor Pathway Inhibitor
Facilitated by the endothelial protein C receptor (EPCR)
Thrombomodulin
Serves as a cofactor in protein C activation when
bound to thrombin
Thrombomodulin
A glycosaminoglycan that enhances the activity of
antithrombin
Heparan sulfate
Present a smooth, contiguous surface
Vascular endothelium is composed of rhomboid cells
eicosanoid platelet inhibitor
Prostacyclin
A vascular “relaxing” factor
Nitric oxide
An anticoagulant that regulates thrombin generation
heparan sulfate
A regulator of the extrinsic pathway of coagulation
TFPI
An integral component of the protein C control system
EPCR
A protein C coagulation control system activator
Thrombomodulin
Activate fibrinolysis
TPA
Procoagulant Properties of Vascular Intima
Vasoconstriction
Collagen
Von Willebrand Factor (vWF)
ADAMTS-13
P-selectin
Intercellular adhesion molecules (ICAMs)
Platelet endothelia cell adhesion molecules (PECAMs)
Smooth muscle cells and fibroblasts
Tissue Factor
Induced by a harmful local stimulus (mechanical or chemical)
Vasoconstriction
Produced by fibroblasts
Collagen
Binds and activates platelets
Collagen
● ADAMTS 13 Secreted by endothelial cells from its storage site called __________
Weibel-Palade bodies
Primarily binds to platelet membrane receptor GPIb to
promote adhesion
Von willebrand factor
Functions as a carrier to factor VIII
Von willebrand factor
Adamts-13 is secreted from
ENDOTHELIAL CELLS
Serves an important function as it cleaves large vWF multimers into shorter chains that support normal platelet adhesion.
ADAMTS-13
Secreted by EC
ADAMTS-13
P-selectin
Intercellular cell adhesion molecules (ICAMs) and Platelet endothelial cell adhesion molecules (PECAMs)
Coats ECs
P-selectin
An adhesion molecule that promotes platelet and
leukocyte-binding
P-selectin
Are immunoglobulin-like adhesion molecules
Intercellular cell adhesion molecules (ICAMs) and Platelet endothelial cell adhesion molecules (PECAMs)
Further promotes platelet and leukocyte binding
Intercellular cell adhesion molecules (ICAMs) and Platelet endothelial cell adhesion molecules (PECAMs)
Supports the constitutive membrane protein tissue factor
Smooth muscle cells and fibroblasts
Disrupted ECs exposes TF in subendothelial cells (activates the coagulation system through contact with factor VII)
Smooth muscle cells and fibroblasts
White clot consists of
Platelet and vwf
Bulky red clot consists of
Consists of platelets, vWF, fibrin, and red blood cells
In arteries and arterioles
White clot
In veins
Bulky red clot
Induce vasoconstriction
Smooth muscle cells in arterioles and arteries
Binds VWF; binds to and activates platelets
Exposed subendothelial collagen
Important for platelet binding to collagen at site of injury: platelet adhesion as a first line of defense against bleeding
Damaged or activated ECs secrete VWF
Promote platelet and leukocyte binding and activation at site of injury P-selectin, ICAMs, PECAMs
Damaged or activated ECs secrete adhesion molecules:
Tissue factor exposed on cell membranes
Exposed smooth muscle cells
and fibroblasts
Tissue factor is induced by inflammation
ECs in inflammation
Fibrinolytic Properties of Vascular Intima
Tissue Plasminogen Activator (TPA)
Plasminogen Activator Inhibitor-1 (PAI-1)
Thrombin Activatable Fibrinolysis Inhibitor (TAFI)
During thrombus formation, both TPA and plasminogen bind to polymerized fibrin
Tissue Plasminogen Activator
Activates fibrinolysis by converting plasminogen to plasmin
Tissue Plasminogen Activator
A TPA control protein that inhibits plasmin generation and fibrinolysis
Plasminogen Activator Inhibitor-1
Increases the tendency for thrombosis
Plasminogen Activator Inhibitor-1
Thrombin Activatable Fibrinolysis Inhibitor
Can slow fibrinolysis
Plasminogen Activator Inhibitor-1
Thrombin Activatable Fibrinolysis Inhibitor
● Is activated by thrombin bound to EC membrane thrombomodulin
Thrombin Activatable Fibrinolysis Inhibitor