HAEMOSTASIS - PLATELET FUNCTION AND COAGULATION

HAEMOSTASIS - PLATELET FUNCTION
AND COAGULATION
HAEMOSTASIS
• the stopping of blood flow
◦ blood clots
• requires 3 compartments
◦ blood vessels
◦ platelets
◦ coagulation factors
• must be tightly controlled


HEALTHY BLOOD VESSEL




DAMAGED BLOOD VESSEL

,• vasoconstriction reduces blood flow
• platelets start to plug the gap
• platelet activation activates coagulation
◦ activates fibrin - which acts as a net and reinforces the plug
• in result a thrombus/blood clot is formed and blood is contained

, PLATELET STRUCTURE




• small
• disc shape
• no nucleus
◦ dont replicate
• plentiful
GRANULES




• secretion dependent on increase in intracellular Ca ions from Ca store
PLATELET STRUCTURE - CYTOSKELETON