Thromb Haemost 1996; 75(03): 497-502
DOI: 10.1055/s-0038-1650304
Original Article
Schattauer GmbH Stuttgart

Effect of Lipoprotein(a) and LDL on Plasminogen Binding to Extracellular Matrix and on Matrix-dependent Plasminogen Activation by Tissue Plasminogen Activator

Hadewijch L M Pekelharing
The Department of Clinical Chemistry, University Hospital Utrecht, Utrecht, The Netherlands
,
Henne A Kleinveld
The Department of Clinical Chemistry, University Hospital Utrecht, Utrecht, The Netherlands
,
Pieter F C.C.M Duif
The Department of Clinical Chemistry, University Hospital Utrecht, Utrecht, The Netherlands
,
Bonno N Bouma
1   The Department of Haematology, University Hospital Utrecht, Utrecht, The Netherlands
,
Herman J M van Rijn
The Department of Clinical Chemistry, University Hospital Utrecht, Utrecht, The Netherlands
› Author Affiliations
Further Information

Publication History

Received 11 September 1995

Accepted after revision 14 December 1995

Publication Date:
26 July 2018 (online)

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Summary

Lp(a) is an LDL-like lipoprotein plus an additional apolipoprotein apo(a). Based on the structural homology of apo(a) with plasminogen, it is hypothesized that Lp(a) interferes with fibrinolysis. Extracellular matrix (ECM) produced by human umbilical vein endothelial cells was used to study the effect of Lp(a) and LDL on plasminogen binding and activation. Both lipoproteins were isolated from the same plasma in a single step. Plasminogen bound to ECM via its lysine binding sites. Lp(a) as well as LDL were capable of competing with plasminogen binding. The degree of inhibition was dependent on the lipoprotein donor as well as the ECM donor. When Lp(a) and LDL obtained from one donor were compared, Lp(a) was always a much more potent competitor. The effect of both lipoproteins on plasminogen binding was reflected in their effect on plasminogen activation. It is speculated that Lp(a) interacts with ECM via its LDL-like lipoprotein moiety as well as via its apo(a) moiety.