The Endothelium Flashcards
What is the endothelium???
A thin membrane that lines the insides of the heart and blood vessels.
What is the function of the endothelial???
It lines the entire vascular network.
Vasoconstriction and vasodilation.
Angiogenesis.
Formation of the blood clots.
Passage of materials in and out of the bloodstream.
Also, a semi-permeable barrier that regulates the movement of small and large molecules.
Why is the physiology of the endothelium particularly important to pharmacists???
Because the capillaries are where most drugs go through to get to their site of action. Capillaries are one cell thick and are composed entirely of endothelium.
What are other specialties of the endothelium???
Homeostasis and coagulation.
Can also metabolise vasoactive substances (Convert angiotensin to angiotensin 1).
What are the molecules synthesised in the vascular endothelium???
Growth factors and cytokines Extracellular matrix and adhesion proteins Anti-coagulation factors Pro-coagulants Vasoactive proteins
What is the role of calcium in Nitric Oxide (NO) release???
This leads to an inhibition of ACh-induced relaxation.
What is the influence of endothelium on VSMC contractility???
In the presence of an endothelial layer the
effect of phenylephrine and nor-adrenaline on
the arterial tone is reduced.
What are the clinical uses of Nitric Oxide (NO)???
Angina
Hypertensive emergencies pulmonary hypertension
CHF
Nitrovasodilators have been used for over 100 years.
How is the endothelium related to diseases???
Most diseases come from inflammation and one of the targets of inflammation is the endothelium.
So endothelial damage and dysfunction normally is a sign of diseases developing.
E.g. endothelial damage can predict the rise of diabetes.
What is the physiology of endothelial cell dysfunction???
The shape of cells changes which opens the endothelial gap junctions which increases vascular permeability.
How does Thrombosis occur???
Through an imbalance between pro and anti-coagulant properties of the endothelium.
What are Common Diseases involving the endothelium???
Hypertension
Atherosclerosis
What are the effects from inflammation???
Nitric oxide release increases.
Superoxide production increases.
Both of these creates Peroxynitrite which initiates cell membrane lipid
peroxidation.
What are the effects from inflammation???
Nitric oxide release increases.
Superoxide production increases.
Both of these creates Peroxynitrite which initiates cell membrane lipid
peroxidation.
