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Updated: Jun 19, 2026
07:03
An in vivo Assay to Test Blood Vessel Permeability
Published on: March 16, 2013
CHANGES IN BLOOD VESSELS (CAPILLARY FRAGILITY) WITH INFLAMMATION.
1Department of Pathology, Cornell University Medical College and New York Hospital, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Inflammation alters skin blood vessel resistance to suction-induced bleeding. Initially, resistance increases, followed by decreased vascular integrity, leading to enhanced capillary fragility and hemorrhage. Allergic inflammation accelerates these changes.
Area of Science:
- Vascular biology
- Dermatology
- Immunology
Background:
- Suction applied to rabbit skin causes intracutaneous hemorrhage.
- Inflammation induced by various agents alters the skin's response to suction.
- Understanding these changes is crucial for studying vascular integrity.
Purpose of the Study:
- To investigate the effects of inflammation on skin vascular resistance to suction.
- To characterize the temporal changes in capillary fragility following inflammatory stimuli.
- To explore the role of inflammation in conditions like the Shwartzman phenomenon.
Main Methods:
- Application of partial vacuum suction (-70 mm. Hg) to rabbit skin.
- Induction of inflammation using diverse agents (turpentine, bacterial components, filtrates).
- Measurement of time to hemorrhage under suction at various time points post-inflammation.
Main Results:
- Normal skin hemorrhages in ~8 minutes; inflammation initially increases resistance (30 min-2 hrs).
- Following initial resistance, capillary fragility increases, causing hemorrhage in 1-4 minutes (12-24 hrs post-injection).
- Capillary fragility duration varies (2-9 days or longer) depending on the inflammatory agent and sensitization.
Conclusions:
- Inflammation significantly alters skin vascular resistance and capillary fragility.
- Allergic inflammation can accelerate and intensify these vascular changes.
- These findings provide insights into vascular injury mechanisms, relevant to phenomena like Shwartzman.
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