🏥 USMLE Exam Prep

During an acute inflammatory response, which of the following is primarily responsible for the immediate increase in vascular permeability, leading to edema and swelling?

A Prostaglandins
B Leukotrienes
C Histamine
D Nitric oxide

✓ Correct Answer: Option C

Histamine, released by mast cells and basophils, is a potent vasoactive amine that causes immediate and transient vasodilation and increased vascular permeability in the initial phase of acute inflammation, leading to edema.

💡 Why is C) the correct answer?

The correct answer to the question "During an acute inflammatory response, which of the following is primarily responsible for the immediate increase in vascular permeability, leading to edema and swelling?" is Option C: Histamine.

The other options — A) Prostaglandins, B) Leukotrienes, D) Nitric oxide — are incorrect for this USMLE Exam Prep question. As explained above: Histamine, released by mast cells and basophils, is a potent vasoactive amine that causes immediate and transient vasodilation and increased vascular permeability in the initial phase of acute inflam…

📚 About This USMLE Exam Prep Practice Question

This 1-level USMLE Exam Prep question from the Step 1 – Basic Sciences topic is part of BrainForge Quiz's free exam preparation library. Each question includes the correct answer and a detailed explanation to help you understand the underlying concept, not just memorize the answer.

How to use this page: Read the question above, consider all four options (A through D), then check the highlighted correct answer and explanation. For active timed practice, start a free USMLE Exam Prep practice test or use flashcards for spaced repetition review.

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