Effects of 5,6 benzo-alphapyrone on traumatic edema due to crush and burn injury

Benzopyrones are a class of drugs which have been used clinically and experimentally in Europe and Australia to reduce tissue swelling caused by high-protein edema states. These drugs are not available nor have they been investigated in the United States. This pilot experiment was designed to determine if one of these compounds, 5,6 benzo-alphapyrone, is effective in reducing traumatic edema from thermal and crush injury.

One hind limb of 34 Sprague-Dawley rats was immersed for 30 seconds in 55 degrees C water and the animals divided into three groups as follows: Group I--no treatment; Group II--17 cc saline/kg body weight IP; Group III--25 mg 5,6 benzopyrone in 17 cc saline/kg body weight IP. In another 30 S-D rats, the soft tissue of the posterior aspect on one hind limb was crushed in a Servistor vise (jaws to within 1 mm of each other) for 5 minutes. They were divided into three groups and treated as in the thermal injury group. After 24 hours both limbs were amputated, weighed, dried, and reweighed. Crushed and burned rat hind limbs treated with benzopyrone after injury had significantly greater dry weights (less edema) than did untreated or saline treated limbs. Benzopyrone appears to be effective in reducing edema following crush and thermal injury in this experimental system. Further studies are being conducted to elucidate the mechanism of action of benzopyrones, their potential activity in other postinjury edema, and their effect on tissue survival.