Which sequence describes the vascular response during inflammation?

Which sequence describes the vascular response during inflammation?

• A. Vasoconstriction followed by vasodilation; leukocytes migrate; fluid accumulates
• B. Vasodilation only
• C. Vasoconstriction only
• D. No vascular change

Answer: (A)

Inflammation triggers changes in the small vessels to bring immune cells to the injured area. The sequence begins with a brief vasoconstriction of the arterioles, which is then followed by rapid vasodilation. This dilation increases blood flow to the site, causing redness and heat. At the same time, chemical mediators (like histamine) make the vessel walls more permeable, so fluid leaks into the surrounding tissue, producing edema. As the vessels become more permeable, white blood cells marginate along the endothelium and migrate out into the tissue to address the injury. This combination—brief vasoconstriction then vasodilation, leukocyte migration, and fluid accumulation—best describes the vascular response during inflammation.

Inflammation triggers changes in the small vessels to bring immune cells to the injured area. The sequence begins with a brief vasoconstriction of the arterioles, which is then followed by rapid vasodilation. This dilation increases blood flow to the site, causing redness and heat. At the same time, chemical mediators (like histamine) make the vessel walls more permeable, so fluid leaks into the surrounding tissue, producing edema. As the vessels become more permeable, white blood cells marginate along the endothelium and migrate out into the tissue to address the injury. This combination—brief vasoconstriction then vasodilation, leukocyte migration, and fluid accumulation—best describes the vascular response during inflammation.