Ch.3 Hemodynamic Disorder Pt.2 Flashcards
Vasodialator, increases vascular permeability, modulator of pain
Bradykinin
Bradkykinin is degraded by what enzyme?
Angiotensen Converting Enzyme (ACE)
Vasoconstrictor! Opposite effect of bradykinn
Use of _____ raise the bodys level of bradykinin
ACE inhibitors. No enzymes secreted= no degredation of Bradykinin.
If levels of bradykinin in the body get to high, this can leave to a dangerous side effect; swelling of deep layers of skin
Angioedema
Bradykinin can also be degraded by ____ inhibitors from the complement system.
C1 Inhibitor
A deficiency in C1 inhibitor can cause what?
Hereditary Angioedema
What is the coagulation factor that activates coagulation cascade, and also activates the pathway that forms bradykinin?
Link between the coagulation & inflammation
Hagman factor XII
- Rare condition
- Markedly **prolonged PTT **(intrinsic pathway)
- **XII cannot **acitvate normally
- Coagulation deficiency
Prekallikrein deffinceny (PK deficiency)
Hagman factor XII requires what two things to generate bradykiin?
- Prekallikrein (PK)
- Hime molecular weight Kinogen (HMWK)
Prekallikrein deffinceny (PK deficiency) causes what to go up?
PTT
Thrombin does what ?
Fibrogen to cross linked fibrogen, amplifying generation of fibrin.
Activates Factor 5, 8, 11, stabalize clot activates 13
. Thrombin is a potent inducer of what?
Patlet activation
Features of what?
- Can mediate effects & contibute to tissue repair
- Anticoagulant effect; prevents clot from extending from site of injury
Thrombin
What factor that limits coagulation?
blood flowing past the site of injury washes out activated coagulation factors, which are rapidly removed by the liver
Simple Dilution
What factor that limits coagulation?
____ which are provided mainly by activated platelets, which are not present away from the site of injury.
negatively charged phospholipids
limits the size of the clot and contributes to itslater dissolution
fibrinolytic cascade
Fibrinolysis is accomplished largely through the enzymatic activity of _____ which breaks down fibrin and interferes with its polymerization.
plasmin,
Fibrin derived breakdown product of fibrogens,
good clinical marker for diffrent thrombotic states and to see if thrombosis was resolbed
D-Dimers
an inactive circulating precursor, by enzymatic cleavage that forms plasmin.
plasminogen
Where is tissue plasminogen activator t-PA? When is it most active?
t-PA is synthezised by endothelium and most active when bound to fibrin
Explain thromosis and antithrombotic properties of the endothelium.
There is a balance between anticoagulant and procoagulant activities of the endothelium
- Normal endothelial cells express factors that inhibit procoagulant activity of platelets and coagulation factors that augment firbinolysis= prevent thrombosis and limit vasucular damage
- If damaged, endothelial cells Lose their antithrombotic properties
WHat are the 3 effects of difrrent antithrombotic agents?
- Platlet inhibtion
- Anticoagulant effects
- Fibrinolytic effects
Release of:
* Prostacyclin (PGI2)
* Nitric Oxide (NO)
* Adenosin
* Binding of thrombin
By the endothelium all do what?
inhibit platlet aggregation
Adenosine degrades ADP and PGL2 & NO are vasodialators thus promoting
washout of coagulation factors. Thrombin bound inhibits ability to actiavtes platlets
What do
* Thrombomodulin
* Endotehlial C-Receptors
* Heprin Like molecules
on endothelium surface do?
bind
* thrombin
and
* protein C
respectively, in complexes on the endothelial cell surface.
Antitrhombosis
Anticoagulation effect
What occurs when thrombomoduline binds thrombin on the endothelial surface?
When thrombin is bound it loses the abilit to activate coagulation factors & platlets, instead it cleaves & activates protein C (with cofactor protien S)
protein C/S complex is a potent inhibitor of coagulation factors
Anticoagulant Effect
What do heprin like molecules on the surface of endothelum do?
Inactivate thrombin and other coagulationf actros by binding and activating Antithrombin III