Rapid Determination of Profibrinolysin (Plasminogen) in Plasma^[*]

Summary

A determination of Profibrinolysin in plasma is described, based on activation of euglobulin precipitate with urokinase and estimation of the obtained fibrinolytic activity by means of the initial lysis of fibrinogen. This was measured by means of the rapid decrease of turbidity in 25% saturated ammonium sulfate in diluted samples taken each minute for the first 6 min of the reaction. The results indicate a large excess of antifibrinolysin over Profibrinolysin in normal plasma.

^* Supported by USPHS grant HE 06238.

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