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Updated: Jul 25, 2026
05:12
Intravital Microscopy of Leukocyte-endothelial and Platelet-leukocyte Interactions in Mesenterial Veins in Mice
Published on: August 13, 2015
Platelets modulate ischemia/reperfusion-induced leukocyte recruitment in the mesenteric circulation
J W Salter1, C F Krieglstein, A C Issekutz
1Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130, USA.
American Journal of Physiology. Gastrointestinal and Liver Physiology
|November 14, 2001
Summary
Ischemia/reperfusion injury involves P-selectin on platelets adhering to endothelial cells, promoting leukocyte recruitment. Blocking this interaction reduces injury, highlighting a key mechanism in gut I/R damage.
Area of Science:
- Vascular Biology
- Immunology
- Gastroenterology
Background:
- Leukocyte-endothelial cell adhesion, mediated by P-selectin, contributes to ischemia/reperfusion (I/R) injury.
- Platelet-endothelial cell adhesion also occurs in postischemic venules, suggesting a role for platelet P-selectin in leukocyte recruitment.
Purpose of the Study:
- To investigate the role of platelet-associated P-selectin in mediating leukocyte recruitment during gut ischemia/reperfusion (I/R) injury.
- To determine if blocking P-selectin or related platelet receptors affects I/R-induced neutrophil accumulation.
Main Methods:
- Measuring P-selectin expression and neutrophil accumulation (myeloperoxidase activity) in postischemic rat intestines.
- Utilizing monoclonal antibodies (MAbs) against P-selectin, GPIIb/IIIa, fibrinogen, and an Arg-Gly-Asp peptide.
- Employing intravital microscopy to observe leukocyte-endothelial cell adhesion and emigration in mesenteric venules.
- Inducing thrombocytopenia to assess the role of platelets.
Main Results:
- I/R-induced increases in P-selectin expression and neutrophil accumulation were significantly reduced by MAbs targeting P-selectin, GPIIb/IIIa, or fibrinogen.
- Intravital microscopy confirmed that MAbs against P-selectin, GPIIb/IIIa, fibrinogen, and an Arg-Gly-Asp peptide attenuated leukocyte adherence and emigration.
- Thrombocytopenia reduced leukocyte emigration but not adherence, indicating platelet P-selectin's role in migration.
Conclusions:
- Ischemia/reperfusion-induced neutrophil recruitment in the gut is a platelet-dependent, P-selectin-mediated process.
- Platelet-associated P-selectin contributes to leukocyte accumulation in postischemic tissue by enhancing transendothelial migration.
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