Magnesium Inhibits Arterial Thrombi after Vascular Injury in Rat: In Vivo Impairment of Coagulation

Summary

Magnesium deficiency is associated with a high frequency of cardiac arrhythmia, hypertension and sudden ischemic death. We investigated the in vivo effects of intravenous magnesium administration in a rat model of chemically induced (FeCl₃) carotid thrombosis. The infusion of magnesium sulfate (MgSO₄) before the topical application of FeCl₃ prevented thrombus formation at concentrations of 0.3 M and 0.6 M, and delayed it even at 0.15 M. Similar results were obtained with MgCl₂. The infusion of MgSO₄ 0.6 M seven minutes after FeCl₃ application delayed but did not prevent thrombus formation. MgSO₄ slightly reduced platelet aggregation ex vivo without affecting plasma clotting tests, but in vivo blood clotting time was markedly prolonged (tail transection method), thus indicating profoundly impaired coagulation. These data provide a rationale for the use of magnesium as an anti-thrombotic agent, but its pharmacological effect critically depends on the timing of administration.

Keywords

Magnesium - thrombosis - animal model - platelets - coagulation

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