PSL301H1 Lecture 6: Hemostasis (Jan. 18, 2017)
41
PSL301H1 Full Course Notes
Verified Note
41 documents
Document Summary
Tutorials start monday (jan. 23, 25, 27) and signup on portal. Dr. heximer starts on friday - watch video posted to prep. Dave - 55yo with a mild heart attack. Arachidonic acid comes from our diet to be converted into: Prostaglandins, thromboxane a2, prostacyclin - bio active molecules. Cyclooxygenase also works to facilitate this conversion process. Aspirin reduces activity of cyclooxygenase, resulting in less bio active mols. This can reduce risk of subsequent heart attacks bc it can, eg, reduce vasoconstriction and platelet aggregation via inhibiting thromboxane a2 synthesis. Thromboxane a2 and prostacyclin have opposing effects, but blood clotting is predominant because platelets are fragments of cells and can"t renew cyclooxygenase (cell systems aren"t present - nucleus, eg) Endothelial cells can readily regenerate cyclooxygenase so prostacyclin levels aren"t as drastically affected. Net effect: less platelet adhesion and vasodilation. Kristy: von willebrand and coagulation (see: coagulation phase) Kristy - 18yo skater with von willebrand disease.
