Warfarin and Heparin Interaction with Prostacyclin-Like Activity Generated by Arterial Wall in the Rat

Summary

A study was performed to evaluate the hypothesis that heparin opposes uncontrolled PGI₂ production by vessels due to thrombin generation. We treated animals with warfarin, an inhibitor of liver synthesis of prothrombin and other vit. K-dependent clotting factors. In fact, if thrombin is presumed to be the stimulus for PGI₂ production, warfarin should suppress this effect. As warfarin treatment did not affect significantly PGI₂-like activity, we conclude that a different hypothesis is necessary to explain the phenomenon. On the other hand, i. p. sodium heparin effectively induced a decrease in PGI₂-LA synthesis, whereas s. c. calcium heparin did not significantly influence it.

Keywords

Warfarin - Heparin - Prostacyclin-like activity - Aorta rat platelets

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