During hemorrhagic shock, which mechanism explains why blood pressure initially drops sharply but then partially recovers due to widespread vasoconstriction of systemic arterioles?

💡 Explanation

Sympathetic activation increases vessel constriction due to norepinephrine binding to alpha-1 receptors on arteriolar smooth muscle cells, therefore raising resistance and partially restoring blood pressure; rather than the other options, this rapid response counteracts blood loss.

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