Analyze Diet
Veterinary research communications1988; 12(2-3); 101-107; doi: 10.1007/BF00362788

Platelet activating factor as a mediator of equine cell locomotion.

Abstract: Equine polymorphonuclear (PMN) and mononuclear (MN) leucocytes were separated on Percoll gradients and used to study the chemoattractant properties of the polar ether-linked phospholipid, platelet activating factor (PAF). Six concentrations of PAF ranging from 1 ng/ml to 100 micrograms/ml were studied in each of two in vitro assay systems, the agarose microdroplet and a microfilter technique. Very significant (p less than 0.01) increases in the movement of both PMN and MN cells were obtained with most concentrations of PAF. In two instances there was no apparent concentration-response relationship, although the action of PAF was approximately bell-shaped in two others. The possible significance of these findings for equine inflammatory conditions is discussed.
Publication Date: 1988-01-01 PubMed ID: 3188378DOI: 10.1007/BF00362788Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Comparative Study
  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

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

APA
Dawson J, Lees P, Sedgwick AD. (1988). Platelet activating factor as a mediator of equine cell locomotion. Vet Res Commun, 12(2-3), 101-107. https://doi.org/10.1007/BF00362788

Publication

ISSN: 0165-7380
NlmUniqueID: 8100520
Country: Switzerland
Language: English
Volume: 12
Issue: 2-3
Pages: 101-107

Researcher Affiliations

Dawson, J
  • Royal Veterinary College, University of London, Great Britain.
Lees, P
    Sedgwick, A D

      MeSH Terms

      • Animals
      • Chemotaxis, Leukocyte
      • Horses / blood
      • Leukocytes, Mononuclear / physiology
      • Neutrophils / physiology
      • Platelet Activating Factor / pharmacology

      References

      This article includes 19 references
      1. Sedgwick AD, Dawson J, Lees P. Influence of chemotactic agents on the locomotion of equine polymorphonuclear and mononuclear leucocytes.. Res Vet Sci 1987 Jul;43(1):55-8.
        pubmed: 3628984
      2. Hopkins NK, Schaub RG, Gorman RR. Acetyl glyceryl ether phosphorylcholine (PAF-acether) and leukotriene B4-mediated neutrophil chemotaxis through an intact endothelial cell monolayer.. Biochim Biophys Acta 1984 Sep 14;805(1):30-6.
        pubmed: 6089913doi: 10.1016/0167-4889(84)90033-8google scholar: lookup
      3. Chignard M, Le Couedic JP, Tence M, Vargaftig BB, Benveniste J. The role of platelet-activating factor in platelet aggregation.. Nature 1979 Jun 28;279(5716):799-800.
        pubmed: 377104doi: 10.1038/279799a0google scholar: lookup
      4. Smith MJ, Walker JR. The effects of some antirheumatic drugs on an in vitro model of human polymorphonuclear leucocyte chemokinesis.. Br J Pharmacol 1980 Jul;69(3):473-8.
      5. Mencia-Huerta JM, Benveniste J. Platelet-activating factor and macrophages. I. Evidence for the release from rat and mouse peritoneal macrophages and not from mastocytes.. Eur J Immunol 1979 May;9(5):409-15.
        pubmed: 385330doi: 10.1002/eji.1830090512google scholar: lookup
      6. McManus LM, Hanahan DJ, Demopoulos CA, Pinckard RN. Pathobiology of the intravenous infusion of acetyl glyceryl ether phosphorylcholine (AGEPC), a synthetic platelet-activating factor (PAF), in the rabbit.. J Immunol 1980 Jun;124(6):2919-24.
        pubmed: 7373056
      7. Halonen M, Palmer JD, Lohman IC, McManus LM, Pinckard RN. Differential effects of platelet depletion on the physiologic alterations of IgE anaphylaxis and acetyl glyceryl ether phosphorylcholine infusion in the rabbit.. Am Rev Respir Dis 1981 Oct;124(4):416-21.
        pubmed: 7294504doi: 10.1164/arrd.1981.124.4.416google scholar: lookup
      8. Lynch JM, Lotner GZ, Betz SJ, Henson PM. The release of a platelet-activating factor by stimulated rabbit neutrophils.. J Immunol 1979 Sep;123(3):1219-26.
        pubmed: 469247
      9. Vargaftig BB, Lefort J, Chignard M, Benveniste J. Platelet-activating factor induces a platelet-dependent bronchoconstriction unrelated to the formation of prostaglandin derivatives.. Eur J Pharmacol 1980 Jul 25;65(2-3):185-92.
        pubmed: 6995139doi: 10.1016/0014-2999(80)90391-xgoogle scholar: lookup
      10. Sedgwick AD, Morris T, Russell BA, Lees P. Single step purification procedure for the rapid separation of equine leucocytes.. Vet Res Commun 1986 Nov;10(6):445-52.
        pubmed: 3798735doi: 10.1007/BF02214007google scholar: lookup
      11. Henson PM. Release of vasoactive amines from rabbit platelets induced by sensitized mononuclear leukocytes and antigen.. J Exp Med 1970 Feb;131(2):287-306.
        pubmed: 5419850doi: 10.1084/jem.131.2.287google scholar: lookup
      12. Shaw JO, Pinckard RN, Ferrigni KS, McManus LM, Hanahan DJ. Activation of human neutrophils with 1-O-hexadecyl/octadecyl-2-acetyl-sn-glycerol-3-phosphorylcholine (platelet activating factor).. J Immunol 1981 Sep;127(3):1250-5.
        pubmed: 6267133
      13. Zigmond SH, Hirsch JG. Leukocyte locomotion and chemotaxis. New methods for evaluation, and demonstration of a cell-derived chemotactic factor.. J Exp Med 1973 Feb 1;137(2):387-410.
        pubmed: 4568301doi: 10.1084/jem.137.2.387google scholar: lookup
      14. Sedgwick AD, Edwards JC, Willoughby DA. Studies on the ability of inflammatory exudate obtained from acute and chronic phases of the inflammatory process to promote leukocyte locomotion in vitro.. Inflammation 1982 Mar;6(1):13-20.
        pubmed: 7085042doi: 10.1007/BF00910715google scholar: lookup
      15. Alam I, Smith JB, Silver MJ. Metabolism of platelet-activating factor by blood platelets and plasma.. Lipids 1983 Aug;18(8):534-8.
        pubmed: 6413803doi: 10.1007/BF02535393google scholar: lookup
      16. Lotner GZ, Lynch JM, Betz SJ, Henson PM. Human neutrophil-derived platelet activating factor.. J Immunol 1980 Feb;124(2):676-84.
        pubmed: 7356708
      17. Hanahan DJ, Demopoulos CA, Liehr J, Pinckard RN. Identification of platelet activating factor isolated from rabbit basophils as acetyl glyceryl ether phosphorylcholine.. J Biol Chem 1980 Jun 25;255(12):5514-6.
        pubmed: 7380824
      18. Benveniste J, Tencé M, Varenne P, Bidault J, Boullet C, Polonsky J. [Semi-synthesis and proposed structure of platelet-activating factor (P.A.F.): PAF-acether an alkyl ether analog of lysophosphatidylcholine].. C R Seances Acad Sci D 1979 Nov 26;289(14):1037-40.
        pubmed: 121258
      19. Benveniste J, Henson PM, Cochrane CG. Leukocyte-dependent histamine release from rabbit platelets. The role of IgE, basophils, and a platelet-activating factor.. J Exp Med 1972 Dec 1;136(6):1356-77.
        pubmed: 4118412doi: 10.1084/jem.136.6.1356google scholar: lookup

      Citations

      This article has been cited 1 times.
      1. 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.
        pubmed: 2174292