Zikria B A, Subbarao C, Oz M C, Shih S T, McLeod P F, Sachdev R, Freeman H P, Hardy M A
Department of Surgery, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Crit Care Med. 1989 Dec;17(12):1306-9. doi: 10.1097/00003246-198912000-00012.
We studied the effect of iv administration of biodegradable macromolecules on microvascular permeability after ischemia-reperfusion injury in a rat gastrocnemius model. After 2 h of tourniquet ischemia of the rats' hind limb, groups of animals were given iv lactated Ringer's solution (RL), serum albumin 5%, or varying MW fractions of biodegradable macromolecules of hydroxyethyl starch (HES), glycogen, and dextran. At the conclusion of the 24-h reperfusion period, the rat gastrocnemius muscles were collected. Water and K+ differences between the ischemic and control muscles were compared. Rats given a 100,000 to 300,000-dalton fraction of HES had significantly decreased water content (5.1 +/- 3.4%) when compared to rats receiving RL (8.3 +/- 2.2, p less than .01), less than 100,000 dalton HES (8.3 +/- 3.2, p less than .05), less than 300,000 glycogen (7.9 +/- 2.5, p less than .01), or dextran 150,000 (8.3 +/- 1.5, p less than .05). Rats given 100,000 to 300,000-dalton HES also had significantly higher ischemic muscle K+ content as compared to the nontourniquet control (difference 14.2 +/- 9.7 mEq/g) than rats receiving any of the other solutions (range 32.5 to 39.3) except the 300,000 to 1,000,000-dalton fraction of HES. Regression analysis comparison of K+ difference to the histologic evaluation of the muscles on the criteria of polymorphonuclear infiltration and interstitial edema (0, best; 3, worst) had a Pearson correlation coefficient of r = .73. Reduction of abnormally increased microvascular permeability may be accomplished by the iv use of appropriate sized biodegradable macromolecules.
我们在大鼠腓肠肌模型中研究了静脉注射可生物降解大分子对缺血再灌注损伤后微血管通透性的影响。在对大鼠后肢进行2小时的止血带缺血处理后，将动物分组并静脉注射乳酸林格氏液（RL）、5%血清白蛋白，或不同分子量级分的可生物降解大分子，包括羟乙基淀粉（HES）、糖原和右旋糖酐。在24小时再灌注期结束时，收集大鼠的腓肠肌。比较缺血肌肉与对照肌肉之间的水分和钾离子差异。与接受RL（8.3±2.2，p<0.01）、分子量小于100,000道尔顿的HES（8.3±3.2，p<0.05）、分子量小于300,000的糖原（7.9±2.5，p<0.01）或150,000道尔顿的右旋糖酐（8.3±1.5，p<0.05）的大鼠相比，接受100,000至300,000道尔顿级分HES的大鼠的含水量显著降低（5.1±3.4%）。与非止血带对照相比，接受100,000至300,000道尔顿HES的大鼠的缺血肌肉钾离子含量也显著更高（差异为14.2±9.7 mEq/g），高于接受任何其他溶液的大鼠（范围为32.5至39.3），但300,000至1,000,000道尔顿级分的HES除外。根据多形核白细胞浸润和间质水肿标准（0，最佳；3，最差），对肌肉进行组织学评估，将钾离子差异与该评估结果进行回归分析比较，皮尔逊相关系数r = 0.73。静脉使用合适大小的可生物降解大分子可能会降低异常增加的微血管通透性。
