Experimental Thrombocytopenia Induced by Busulphan (Myleran) in Rabbits: Extremely Low Platelet Levels and Intact Plasma Clotting System^[*]

Summary

The effects of 2 intraperitoneal injections of the alkylating agent Busulphan (each of 25 mg/kg body weight, 3 days between injections) on the circulating elements of the blood and on the plasma coagulation system in rabbits have been investigated.

Platelets fell progressively after a lag-phase of 7 days, reached a mean minimum level of about 3 % of the pre-injection level in 14 days, and then returned slowly towards normal values. Bleeding was an occasional complication and a rare cause of death. Granulocytopenia developed synchronously with the fall in platelets. The plasma clotting factors remained intact.

We conclude that this is a useful experimental model for studies on the role of platelets in hemostasis and thrombosis.

^* Supported by The Norwegian Research Council for Science and the Humanities and by the Norwegian Council on Cardiovascular Diseases.

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