减阻剂对急性失血性休克合并内毒素致伤大鼠微循环的作用

目的观察减阻剂对急性失血性休克合并内毒素致伤大鼠皮肤微循环的改善作用及抗氧化能力。方法 60只SD大鼠,雌雄不拘,体质量（302±26）g,用简单随机法随机分为A、B、C三组,每组20只。在30 min内自颈动脉放血完成失血性休克,最终的指标为平均动脉压（40±5）mmHg,然后静脉给予内毒素10 mg/kg,休克30 min后开始液体复苏。复苏时间为5 min。A组静脉给予3.5 ml/kg的生理盐水;B组使用内含0.4 mg/ml的透明质酸和0.05 mg/ml聚氧化乙烯作为减阻剂的等量生理盐水复苏;C组使用内含芦荟提取物0.05 mg/ml的等量生理盐水复苏。在不同时间点,使用激光多普勒血流仪观察大鼠左侧腹股沟皮肤灌注情况,并测定大鼠血清超氧化物歧化酶（SOD）和丙二醛（MDA）浓度。结果 A、B、C三组的生存率分别为15%、55%和60%。三组的MDA和SOD在失血性休克开始后均显著升高并持续至实验结束。与A组比较,B和C组应用减阻剂60min后皮肤血流灌注得到改善并维持至实验结束,B和C组的SOD显著高于A组,MDA显著低于A组。结论减阻剂可在急性失血性休克复合内毒素大鼠模型中,提高大鼠生存率、有效改善大鼠的皮肤微循环、增强抗氧化能力。

Effect of drag reducing polymer on the microcirculation in rat model of com- bined acute severe hemorrhagic shock and endotoxin infusion

Objective To observe the effect of drag reducing polymer （DRP） on the microcirculation and its＇ antioxidative function in rat model of combined acute severe hemorrhagic shock and endotoxin infusion. Methods Sixty SD rats of both sexes weighing （302 ± 26） g were assigned to A, B, C groups of twenty animals in each group by simple randomization method. The caudal vein was cannulated with polyethylene tubing to administer drugs and fluids. The rats were anesthetized with intravenously administered Pentothal sodium 30mg/kg intermittently. Right common carotid artery was cannulated for BP monitoring, blood removal and blood sampling. Acute severe hemorrhagic shock was induced by removal of blood in 30 min and the aim of the shock was MAP（40 ±5 ） mmHg. After that, endotoxin 10mg/kg was given intravenously via the caudal vein. After 30 min＇ s period of shock, resuscitation was carried out within 5 min： group A resuscitated with 3.5 ml/kg normal saline; group B resuscitated with 3.5 ml/kg of normal saline and Hyaluronic Acid （HA） 0.4mg/ml and Polyethylene oxide （PEO） 0.05 mg/ml; group C resuscitated with 3.5 ml/kg normal saline and 0.05mg/ml DRP extracted from aloe vera. A laser Doppler tissue perfusion probe was placed on the left groin area. At different time points, the skin microcirculation parameters were recorded and the serum malondialdehyde （MDA） and superoxide dismutase （SOD） levels were measured. Results The survival rate in group A, B and C were 15%, 55% and 60% respectively. In group B and C, the skin microcirculation improved significantly from the time point of 60 minutes after the end of resuscitation, and the improvement lasted to the end of the experiment. In all of the three groups, MDA and SOD levels increased from the shock period and lasted to the end of the study. However, after 60 minutes from the resuscitation, the MDA levels in group B and C were higher than those in group A. Contrast to the MDA, the SOD concentration in group B and C were higher than that in group A from that point to the end of the experiment. Conclusion In the rat model of combined acute hemorrhagic shock and en-dotoxin infusion, DRP could enhance the survival rates, improve the skin microcirculation, and increase the antioxidative function.