The Effects of 21-Aminosteroid U74389F on Posttraumatic Spinal Cord Blood Flow and Somatosensory Evoked Potential

Joo, Jin Yang; Kim, Young Soo

Abstract

A growing body of biochemical, physiological, and pharmacological evidence has suggested that oxygen free radical-induced lipid peroxidation plays a key role in progressive posttraumatic spinal cord ischemia. Recently, it has been reported that the newly developed compound, U74006 F, a non-glucocorticoid 21-aminosteroid, is extremely potent as an inhibitor of lipid peroxidation and effective preventor from the posttraumatic ischemia. In this investigation, the effects of 21-aminosteroid U74389F, analog of U74006F on posttraumatic spinal cord blood flow and somatosensory evoked potential have been studied in cats. The results of this study are summarized as follows:(1) U74389F, given 3 mg/kg, blood flow decreased significantly and somatosensory response returned to none of five cats. (2) U74389F, given 10 mg/kg or 20 mg/kg, the blood flow did not decreased and maintained near the preinjury level. The recovery rate of somatosensory evoked potential ranged from 40 to 60%. (3) There was no statistical difference of blood flow change between the cats treated with 10 mg/kg and those treated with 20 mg/kg of U74389F. It is thought that the adequate dosage of U74389F to prevent posttraumatic spinal cord ischemia is more than 10 mg/kg or 20 mg/kg of U74389F, was statistically significant compared to much more decrease in naloxone-treated cats. The reason is thought to be much longer half life of U74389F in serum. From the above results, it is speculated that U74389Fhas beneficial effect on posttraumatic spinal cord ischemia and functional recovery. The effects last longer than those of naloxone.