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What is Following injury to blood vessels , immediate haemostasis is achieved by which of the following and explain in detail?
ref Robbins 8/e p115 Vascular spasm (Vasoconstriction) -Vasoconstriction is produced by vascular smooth muscle cells, and is the blood vessel's first response to injury. ... When a blood vessel is damaged, there is an immediate reflex, initiated by local sympathetic pain receptors, which helps promote vasoconstriction