Isolation of prostaglandin E2-like material from osteonecrosis induced by steroids and its prevention by kallikrein-inhibitor, aprotinin. An experimental study in rabbits.

Prostaglandin E2 (PGE2)-like activity was measured in osteonecrotic femoral heads caused by high doses of methyl prednisolone acetate in rabbits. Serum levels of cholesterol, total lipids, free fatty acids, alkaline phosphatase, SGOT and lipase were also determined. There were increases in local tissue PGE2-like activity, serum cholesterol, total lipid and free fatty acid levels in rabbits with steroid-induced osteonecrosis as compared to the controls. The rabbits given aprotinin together with the steroid showed significant decreases in serum cholesterol and lipid levels coupled with a marked increase in the local PGE2-like activity. Aprotinin prevented osteonecrosis induced by steroids. The results are discussed in the light of the relevant literature.