Skjeldal S, Torvik A, Nordsletten L, Kirkeby O J, Grøgaard B, Svindland A, Reikerås O
Institute for Surgical Research, National Hospital, Oslo, Norway.
Res Exp Med (Berl). 1993;193(2):73-80. doi: 10.1007/BF02576213.
A modified rat hindlimb tourniquet model was used to measure postischemic muscle necrosis. The effect of moderate local hypothermia to 20 degrees C during ischemia and reperfusion was investigated. Eighteen animals were kept in an incubator at 27 degrees C, and complete circulatory arrest was maintained for 3.5 h before release of the vascular occlusion. After survival for 72 h the degree of necrosis in the anterior tibial muscles was measured morphometrically on histological slides. Areas of necrosis with intact capillary structure and resorption of muscle fibers, and areas without resorption and capillary disintegration were measured separately. Three experimental groups (six animals in each) were included in the series. In the first group local cooling to 20 degrees C was performed during the initial 1.5 h of ischemia. The second group was cooled for 1.5 h during the initial phase of reperfusion. The animals in the third group served as controls without cooling. The total areas of necrosis in the three groups were 0, 90 and 90%, and the areas of no-resorption 0, 23 and 39%, respectively. Cooling during ischemia thus had a marked effect, while no significant differences were found between the control group and the group cooled during reperfusion. The study shows that moderate cooling during initial ischemia protects effectively against postischemic muscle necrosis, while cooling during reperfusion has no such effect.
采用改良的大鼠后肢止血带模型来测量缺血后肌肉坏死情况。研究了在缺血和再灌注期间将局部温度适度降低至20摄氏度的效果。18只动物饲养在27摄氏度的培养箱中，在解除血管闭塞前维持完全循环阻断3.5小时。存活72小时后，在组织学切片上通过形态计量学测量胫前肌的坏死程度。分别测量具有完整毛细血管结构且肌肉纤维有吸收的坏死区域，以及无吸收且毛细血管崩解的区域。该系列研究包括三个实验组（每组6只动物）。第一组在缺血的最初1.5小时内将局部温度降至20摄氏度。第二组在再灌注初期冷却1.5小时。第三组动物作为未冷却的对照组。三组的坏死总面积分别为0%、90%和90%，无吸收区域分别为0%、23%和39%。因此，缺血期间的冷却有显著效果，而对照组和再灌注期间冷却的组之间未发现显著差异。研究表明，缺血初期的适度冷却能有效预防缺血后肌肉坏死，而再灌注期间冷却则无此效果。
