Platelet activating factor as a mediator of equine cell locomotion.
- Comparative Study
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
The research investigates the effects of the phospholipid, platelet activating factor (PAF), on the movement of two types of equine white blood cells. Increased cell movement was observed with most concentrations of PAF, which may have implications for understanding equine inflammatory conditions.
Objective of the Research
The researchers aimed to study the influence of platelet activating factor (PAF) on the locomotion of two types of equine white blood cells, polymorphonuclear (PMN) and mononuclear (MN) leucocytes. The purpose of this study was to advance the understanding of equine cell movement, with a particular focus on the inflammatory response.
Methodology
- The research team isolated PMN and MN leucocytes from horses, employing Percoll gradients for cell separation.
- These cells were then exposed to six distinct concentrations of PAF, ranging from 1 nanogram per milliliter to 100 micrograms per milliliter.
- The effects of PAF on cell locomotion were evaluated using two in vitro assay systems: the agarose microdroplet method and a microfilter technique.
Findings
- Significant increases in cell movement were observed in both PMN and MN leucocytes across most PAF concentrations, indicating PAF’s potency as a chemoattractant.
- Not all lab results demonstrated a concentration-response relationship; the influence of PAF on cell locomotion did not consistently increase with concentration.
- In two instances, the influence of PAF on cell movement followed a bell-shaped curve; the degree of cell locomotion initially increased with concentration, peaked, then decreased.
Implications
These findings potentially carry significance for understanding equine inflammatory conditions, as the movement of leukocytes is essential for the inflammatory response. Increased understanding about the role of PAF in promoting cell movement may further inform veterinarians and equine scientists about how to manage and treat conditions involving inflammation. However, the researchers mention that the relationship between PAF concentration and cell locomotion is not straightforward, and additional investigation is required.
Cite This Article
Publication
Researcher Affiliations
- Royal Veterinary College, University of London, Great Britain.
MeSH Terms
- Animals
- Chemotaxis, Leukocyte
- Horses / blood
- Leukocytes, Mononuclear / physiology
- Neutrophils / physiology
- Platelet Activating Factor / pharmacology
References
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Citations
This article has been cited 1 times.- McEwen BJ, Wilcock BP, Eyre P. The effect of leukotriene B4, leukotriene C4, zymosan activated serum, histamine, tabanid extract and N-formyl-methionyl-leucyl-phenylalanine on the in vitro migration of equine eosinophils. Can J Vet Res 1990 Oct;54(4):400-4.