The effect of hyperlipoproteinemia on thrombolysis: in vitro studies using purified lipoproteins from normolipemic donors.

ABSTRACT

To determine whether or not lipoproteins affect thrombolysis in vitro using Chandler's loop method, VLDL, LDL, and HDL fractions from healthy male donors were obtained by ultracentrifugation. The lipoproteins were used to enrich whole blood or fibrin thrombi radiolabeled with 125-I-fibrinogen. Lipoprotein-enriched or unenriched thrombi were perfused in rotating Chandler loops with lipoprotein-enriched or unenriched plasma, respectively. Lysis was initiated by adding high molecular weight urokinase or single chain pro-urokinase to the perfusion medium. In some experiments, plasminogen was also added. Variation in the amounts of these activators and plasminogen permitted study of the effect of lipoproteins over a range of thrombolysis. No consistent statistically significant difference in the degree or time course of lysis of lipoprotein-enriched vs. unenriched thrombi or perfusion media was found. These studies, using normal lipoproteins, do not preclude the possibility that lipoproteins from patients with type IIa, IIb, or IV hyperlipoproteinemia may be genetically abnormal or may function pathologically, resulting in an effect on thrombolysis.