Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1982 Jun 1;93(3):775–787. doi: 10.1083/jcb.93.3.775

Ultrastructure of clots during isometric contraction

PMCID: PMC2112132  PMID: 6889599

Abstract

We explored the retraction or contraction of platelet-fibrin clots under isometric conditions. In the presence of micromolar calcium clots of normal platelet-rich plasma developed tension at an initial rate of 0.1 to 0.2 g/min per cm2 (initial cross-sectional area). Electron microscopy of clots fixed after attaining a force of 1.6 g/cm2 revealed platelets with elongated bodies and pseudopods in close apposition to fibrin strands which were oriented in cablelike fashion in the direction of tension. The development of tension could not be explained simply on the basis of platelet-platelet association and interaction alone. First, factor XIII-dependent cross-linking of fibrin fibers was critical to normal isometric contraction. Second, tension decreased linearly, rather than exponentially, when the platelet count in the platelet-fibrin clot was decreased, suggesting that platelets must be interacting with another component (i.e. fibrin). Thrombasthenic platelets, deficient in fibrinogen receptors, failed to develop tension or to align fibrin strands or pseudopods in the clot. Platelet-fibrin clots treated with vincristine to disassemble microtubules or cytochalasin B to disrupt microfilaments failed to develop tension and relaxed if these agents were added after tension had developed. Relaxation under these conditions, however, was not associated with loss of orientation of fibrin strands. Our findings suggest that platelet-fibrin interaction in clots under isometric conditions leads to orientation of fibrin strands and platelets in the direction of force generation. Tension develops as platelets simultaneously attach to and spread along fibrin strands, and contract. The contraction draws some fibrin into platelet-fibrin clumps and aligns other strands in the long axis of tension. The achievement and maintenance of maximum tension appears to depend on the development of platelet-fibrin attachments and extension of platelet bodies and long pseudopods containing bundles of microfilaments and microtubules along the oriented fibrin fibers.

Full Text

The Full Text of this article is available as a PDF (1.7 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bennett J. S., Vilaire G. Exposure of platelet fibrinogen receptors by ADP and epinephrine. J Clin Invest. 1979 Nov;64(5):1393–1401. doi: 10.1172/JCI109597. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bohn H., Haupt H. Eine quantitative Bestimmung von Faktor 13 mit Anti-Faktor-13-Serum. Thromb Diath Haemorrh. 1968 Jul 31;19(3):309–315. [PubMed] [Google Scholar]
  3. Brenner S. L., Korn E. D. Substoichiometric concentrations of cytochalasin D inhibit actin polymerization. Additional evidence for an F-actin treadmill. J Biol Chem. 1979 Oct 25;254(20):9982–9985. [PubMed] [Google Scholar]
  4. Carroll R. C., Gerrard J. M., Gilliam J. M. Clot retraction facilitates clot lysis. Blood. 1981 Jan;57(1):44–48. [PubMed] [Google Scholar]
  5. Chao F. C., Shepro D., Tullis J. L., Belamarich F. A., Curby W. A. Similarities between platelet contraction and cellular motility during mitosis: role of platelet microtubules in clot retraction. J Cell Sci. 1976 May;20(3):569–588. doi: 10.1242/jcs.20.3.569. [DOI] [PubMed] [Google Scholar]
  6. Cohen I., De Vries A. Platelet contractile regulation in an isometric system. Nature. 1973 Nov 2;246(5427):36–37. doi: 10.1038/246036a0. [DOI] [PubMed] [Google Scholar]
  7. Cohen I., Glaser T., Veis A., Bruner-Lorand J. Ca2+-dependent cross-linking processes in human platelets. Biochim Biophys Acta. 1981 Aug 17;676(2):137–147. doi: 10.1016/0304-4165(81)90181-1. [DOI] [PubMed] [Google Scholar]
  8. Curtis C. G., Lorand L. Fibrin-stabilizing factor (factor XIII). Methods Enzymol. 1976;45:177–191. doi: 10.1016/s0076-6879(76)45018-8. [DOI] [PubMed] [Google Scholar]
  9. De Clerck F., Borgers M., de Gaetano G., Vermylen J. Dissociation of clot retraction from platelet granule fusion and degranulation: an ultrastructural study of Reptilase-human platelet-rich plasma clots. Br J Haematol. 1975 Feb;29(2):341–348. doi: 10.1111/j.1365-2141.1975.tb01828.x. [DOI] [PubMed] [Google Scholar]
  10. Folk J. E., Finlayson J. S. The epsilon-(gamma-glutamyl)lysine crosslink and the catalytic role of transglutaminases. Adv Protein Chem. 1977;31:1–133. doi: 10.1016/s0065-3233(08)60217-x. [DOI] [PubMed] [Google Scholar]
  11. Fox J. E., Phillips D. R. Inhibition of actin polymerization in blood platelets by cytochalasins. Nature. 1981 Aug 13;292(5824):650–652. doi: 10.1038/292650a0. [DOI] [PubMed] [Google Scholar]
  12. Gerrard J. M., Phillips D. R., Rao G. H., Plow E. F., Walz D. A., Ross R., Harker L. A., White J. G. Biochemical studies of two patients with the gray platelet syndrome. Selective deficiency of platelet alpha granules. J Clin Invest. 1980 Jul;66(1):102–109. doi: 10.1172/JCI109823. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gerrard J. M., Schollmeyer J. V., Phillips D. R., White J. G. alpha-Actinin deficiency in thrombasthenia: possible identity of alpha-actinin and glycoprotein III. Am J Pathol. 1979 Mar;94(3):509–528. [PMC free article] [PubMed] [Google Scholar]
  14. Gerrard J. M., White J. G., Rao G. H., Krivit W., Witkop C. J., Jr Labile aggregation stimulating substance (LASS): the factor from storage pool deficient platelets correcting defective aggregation and release of aspirin treated normal platelets. Br J Haematol. 1975 Apr;29(4):657–665. doi: 10.1111/j.1365-2141.1975.tb02751.x. [DOI] [PubMed] [Google Scholar]
  15. Holmsen H. Biochemistry of the platelet release reaction. Ciba Found Symp. 1975;35:175–205. doi: 10.1002/9780470720172.ch9. [DOI] [PubMed] [Google Scholar]
  16. Jenkins C. S., Meyer D., Dreyfus M. D., Larrieu M. J. Willebrand factor and ristocetin. I. Mechanism of rustocetin-induced platelet aggregation. Br J Haematol. 1974 Dec;28(4):561–578. doi: 10.1111/j.1365-2141.1974.tb06675.x. [DOI] [PubMed] [Google Scholar]
  17. Kirkpatrick J. P., McIntire L. V., Moake J. L., Cimo P. L. Differential effects of cytochalasin B on platelet release, aggregation and contractility: evidence against a contractile mechanism for the release of platelet granular contents. Thromb Haemost. 1980 Feb 29;42(5):1483–1489. [PubMed] [Google Scholar]
  18. LOEWY A. G., DUNATHAN K., KRIEL R., WOLFINGER H. L., Jr Fibrinase. I. Purification of substrate and enzyme. J Biol Chem. 1961 Oct;236:2625–2633. [PubMed] [Google Scholar]
  19. Laurell C. B. Electroimmuno assay. Scand J Clin Lab Invest Suppl. 1972;124:21–37. doi: 10.3109/00365517209102748. [DOI] [PubMed] [Google Scholar]
  20. Marguerie G. A., Edgington T. S., Plow E. F. Interaction of fibrinogen with its platelet receptor as part of a multistep reaction in ADP-induced platelet aggregation. J Biol Chem. 1980 Jan 10;255(1):154–161. [PubMed] [Google Scholar]
  21. Martin J. F., Holland T. K., Russell R. G. Evidence for the involvement of microtubules in the ADP-induced secretion in platelet 14C-5-hydroxytryptamine. Thromb Res. 1981 Jun 1;22(5-6):525–533. doi: 10.1016/0049-3848(81)90050-5. [DOI] [PubMed] [Google Scholar]
  22. Mustard J. F., Kinlough-Rathbone R. L., Packham M. A., Perry D. W., Harfenist E. J., Pai K. R. Comparison of fibrinogen association with normal and thrombasthenic platelets on exposure to ADP or chymotrypsin. Blood. 1979 Nov;54(5):987–993. [PubMed] [Google Scholar]
  23. Mürer E. H. Clot retraction and energy metabolism of platelets. Effect and mechanism of inhibitors. Biochim Biophys Acta. 1969 Feb 25;172(2):266–276. doi: 10.1016/0005-2728(69)90069-3. [DOI] [PubMed] [Google Scholar]
  24. Nachmias V. T. Cytoskeleton of human platelets at rest and after spreading. J Cell Biol. 1980 Sep;86(3):795–802. doi: 10.1083/jcb.86.3.795. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Niewiarowski S., Markiewicz M., Nath N. Inhibition of the platelet-dependent fibrin retraction by the fibrin stabilizing factor (FSF, factor 13). J Lab Clin Med. 1973 May;81(5):641–650. [PubMed] [Google Scholar]
  26. Phillips D. R., Agin P. P. Platelet membrane defects in Glanzmann's thrombasthenia. Evidence for decreased amounts of two major glycoproteins. J Clin Invest. 1977 Sep;60(3):535–545. doi: 10.1172/JCI108805. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Phillips D. R., Jennings L. K., Edwards H. H. Identification of membrane proteins mediating the interaction of human platelets. J Cell Biol. 1980 Jul;86(1):77–86. doi: 10.1083/jcb.86.1.77. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Rao K. M., Newcomb T. F. Clot retraction in a factor XIII free system. Scand J Haematol. 1980 Feb;24(2):142–148. doi: 10.1111/j.1600-0609.1980.tb02358.x. [DOI] [PubMed] [Google Scholar]
  29. Shah N. T., Karpen C. W., Panganamala R. V. In vitro effects of vincristine on arachidonic acid metabolism in human platelets and rat arterial tissue. Thromb Res. 1981 Aug 1;23(3):225–231. doi: 10.1016/0049-3848(81)90012-8. [DOI] [PubMed] [Google Scholar]
  30. Sneddon J. M. Effect of mitosis inhibitors on blood platelet microtubules and aggregation. J Physiol. 1971 Apr;214(1):145–158. doi: 10.1113/jphysiol.1971.sp009424. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. WHITE J. G., KRIVIT W., VERNIER R. L. THE PLATELET-FIBRIN RELATIONSHIP IN HUMAN BLOOD CLOTS: AN ULTRASTRUCTURAL STUDY UTILIZING FERRITIN-CONJUGATED ANTI-HUMAN FIBRINOGEN ANTIBODY. Blood. 1965 Feb;25:241–257. [PubMed] [Google Scholar]
  32. Walsh P. N., Mills D. C., White J. G. Metabolism and function of human platelets washed by albumin density gradient separation. Br J Haematol. 1977 Jun;36(2):287–296. doi: 10.1111/j.1365-2141.1977.tb00649.x. [DOI] [PubMed] [Google Scholar]
  33. White J. G. Effects of colchicine and Vinca alkaloids on human platelets. I. Influence on platelet microtubules and contractile function. Am J Pathol. 1968 Aug;53(2):281–291. [PMC free article] [PubMed] [Google Scholar]
  34. White J. G. Fine structural alterations induced in platelets by adenosine diphosphate. Blood. 1968 May;31(5):604–622. [PubMed] [Google Scholar]
  35. Zeigler Z., Schugar S. The effect of cytochalasin B and alkaloid compounds on human monocyte functions. J Reticuloendothel Soc. 1979 Mar;25(3):235–241. [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES