低氧下冻伤对大鼠骨骼肌水肿程度的影响

EFFECT OF FROSTBITE UNDER HYPOXIA ON EDEMA OF SKELETAL MUSCLE IN RAT

观察了低氧条件下冻伤大鼠骨骼肌水肿程度的改变。体重２００±２０ｇ雄性Ｗｉｓｔａｒ大鼠随机分为三组：平原冻伤组（ＦＮ）；急性低氧冻伤组（ＦＡＨ，模拟海拔６０００ｍ缺氧４ｈ后冻伤）和低氧习服冻伤组（ＦＨＡＣ，模拟海拔６０００ｍ每日缺氧４ｈ，连续４周后冻伤）。大鼠的右后肢冻伤后不同时间，用称量法测定冻伤肌肉中的含水量，计算其水肿程度。结果表明，各冻伤组冻后肌肉水肿程度均明显增加，其中以ＦＮ组较为严重，ＦＡＨ组肌肉水肿程度与ＦＮ组无差别，而ＦＨＡＣ组冻伤肌肉水肿程度较轻且消退较快，组织干性坏死出现较早。结果提示单纯急性低氧未加重冻伤损伤程度，而低氧习服则可加重冻伤损伤程度。

The edema of skeletal mucule of rat hind leg after frostbite injury under hypoxia was investigated. Male Wistar rats weighing 200±20g were randomly divided into three groups: frostbite at normoxia(FN);frostbite during acute hypoxia(4h at simulated altitude of 6 000m,FAH)and frostbite during acute hypoxia after altitude acclimation(exposed to 6 000m 4h daily for 4 weeks,FHAC).The edema of injured muscles was evaluated by weighing method. The results showed that the water content of frostbitten muscles was increased significantly for all groups. There was no difference between FN and FAH groups, but intensity of edema was much lower in FHAC groups and subsided more rapidly due to earlier occurrence of mummification of injured tissues. These results suggested that the degree of cold injury was not aggravated by acute hypoxia, while altitude acclimation for 4 weeks might worsen the conditions.