高压电烧伤对大鼠血小板与白细胞流变性的影响及己酮可可碱的干预作用

Influence of high-voltage electrical burn on the rheological property of platelet and leukocyte in rats and the interventional effect of pentoxifylline

目的了解高压电烧伤对大鼠血小板、白细胞聚集黏附的影响，探讨己酮可可碱（PTX）的干预作用。方法将180只SD大鼠按随机数字表法分为对照组、电伤组和治疗组，每组60只。（1）3组致伤前15min各取10只大鼠，用布莱德多项投影显微镜系统观测肠系膜微静脉白细胞黏附数；用激光多普勒组织灌流图像仪检测胸部皮肤微循环灌流量；心脏采血分离血清，用双抗体夹心ELISA法检测血清中血小板活化因子（PAF）、血栓烷B2（TXB2）、前列环素（PG12）、P选择素、E选择素及L选择素含量，并计算TXB2／PG12比值。（2）电伤组和治疗组余下各50只大鼠用调压器及实验变压器制成高压电烧伤模型（左前肢为电流入口，右后肢为电流出口），对照组余下50只大鼠接相同装置但不通电致假伤。伤后2min内，经腹腔注射2mL生理盐水（对照组、电伤组）或者2mL浓度为50mg／mL PTX注射液（治疗组）。伤后5min和1、2、4、8h于每组各取10只大鼠，同前检测白细胞黏附数和微循环灌流量、血清血小板及白细胞相关因子水平，计算相关比值。对数据行两因素析因设计的方差分析和LSD检验。结果电伤组大鼠PAF、TXB2、PG12、P选择素、E选择素、L选择素含量以及TXB2／PG12比值和白细胞黏附数总体检测值大于对照组；微循环灌流量小于对照组，处理因素主效应F值为854．20～8156．52，P值均小于0．01。治疗组大鼠PAF、TXB2、P选择素、E选择素、L选择素含量以及TXB2／PG12比值和白细胞黏附数总体检测值小于电伤组；PG12含量、微循环灌流照大于电伤组，处理因素主效应，值为33．18—1033．99，P值均小于0．01。统计学结果仅允许在电伤组、治疗组组内进行比较。除治疗组伤后5min TXB2／PG12比值、电伤组和治疗组伤后5min E选择素含量外，电伤组及治疗组大鼠伤后各时相点PAF、TXB2、PG12、P选择素、E选择素、L选择素含量及TXB2／PG12比值和白细胞黏附数显著大于伤前15min；微循环灌流量显著小于伤前15min（P值均小于0．001）。电伤组PAF、TXB2、E选择素含量及TXB2／PG12比值于伤后4h达峰值，分别为（9．3±0．9）ng／mL、（14．31±0．65）nmoL／mL、（271．2±18．4）ng／mL、4．62±0．26；PG12、P选择素含量及每100微米微静脉白细胞黏附数伤后8h达峰值，分别为（3．98±0．24）nmol／mL、（514±24）ng／mL、（25．5±4．14）个；L选择素含量于伤后2h达峰值，为（876±54）ng／mL；微循环灌流量以伤后5min最小，为（1．17±0．10）V。结论高压电烧伤引起大鼠PAF、TXB2、PG12、P选择素、E选择素、L选择素含量及TXB2／PG12比值升高，白细胞黏附数增加及微循环灌流量下降。PTX通过增加PG12的含量，降低上述其他因子的含量而抑制血小板及白细胞聚集黏附，从而改善电烧伤后微循环障碍。

Objective To investigate the influence of high-voltage electrical burn （HEB） on the ag- gregation and adhesion of platelet and leukocyte in rats and the interventional effect of pentoxifylline （ PTX ）. Methods One hundred and eighty SD rats were divided into control, eleetrieai burn （EB） , and pentoxifyl- line treatment （PT） groups according to the random number table, with 60 rats in each group. （ 1 ） Ten rats were taken from each group at 15 minutes before injury for the observation of the microcirculatory perfusion of chest skin with Laser Doppler Perfusion Imager （LDPI） , and the number of leukocyte adherent to mesenteric venule with Bradford Variable Projection Microscope （BVPM）. Serum was collected from heart blood to de- termine the contents of platelet activating factor （PAF）, thromboxane B2 （TXB2）, prostacyclin （PG12）, P-selectin, E-selectin and L-selectin by double-antibody sandwich enzyme-linked immunosorbent assay. The ratio of TXB2 to PG12 was calculated therefrom. （2） Model of HEB was reproduced in the remaining 50 rats of EB group and that of PT group with voltage regulator and experimental transformer （the electrical current applied to the left forelimb and exited from the right hind limb ）. The remaining 50 rats of control group were sham injured with the same devices without electric current. Within 2 minutes post injury （ PIM）, rats in control group and EB group were intraperitoneally injected with 2 mL isotonic saline, while rats in PT group were intraperitoneally injected with 2 mL pentoxifylline （50 mg/mL）. At PIM 5 and 1, 2, 4, 8 hour （s） post injury （PIH） , 10 rats of every group were randomly chosen at each time point for the observation of the microcirculatory perfusion of chest skin and the number of leukocytes adherent to mesenteric venule through the same method as used above, and the levels of the related factors of aggregation and adhesion of platelets and leukocytes were determined, and then the relative ratio was calculated. Data were processed with the a- nalysis of variance of factorial design and LSD test. Results The contents of PAF, TXB2, PG12, P-se- lectin, E-selectin, L-selectin, and the ratio of TXB2 to PG12, as well as the number of adhered leukocyte in EB group were higher, while the microcirculatory perfusion value was lower than those of control group, with F values from 854.20 to 8156.52, P values all below 0.01. The microcirculatory perfusion value and PG12 content of PT group were higher, while the contents or number of other indexes were lower than those of EB group, with F values from 33.18 to 1033.99, P values all below 0.01. Only the data within EB group and PT group were comparable. The contents of PAF, TXB2, PG12, P-selectin, E-selectin, L-selectin, and the ratio of TXB2 to PG12, as well as the number of adhered leukocyte in EB group and PT group at each time point were significantly higher than those at 15 minutes before injury, while the microcirculation perfusion value was significantly lower than that at 15 minutes before injury （ P values all below 0. 001 ）, with the ex- ception of the ratio of TXB2 to PG12 in PT group and E-selectin in EB group and PT group at PIM 5. The contents of PAF, TXB2, and E-selectin and the ratio of TXB2 to PG12 in EB group peaked at PIH 4, and they were respectively （9.3 ±0.9） ng/mL, （14.31 ±0.65） nmol/mL, （271.2±18.4） ng/mL and 4.62 ± 0.26. The contents of PG12 and P-selectin, and the number of adhered leukocyte in EB group peaked at PIH 8, and they were respectively （3.98 ±0.24） nmol/mL, （514 ±24） ng/mL, and （25.50 ±4.14） per 100 μm venule. The content of L-selectin peaked at PIH 2 [ （876 ± 54） ng/mL]. The microcirculatory per- fusion value was lowest at PIM 5 [ （ 1. 17 ± 0. 10） V]. Conclusions HEB can increase the contents of PAF, TXB2, PG12, P-selectin, E-selectin, L-selectin, the ratio of TXB2 to PG12, and the number of ad- hered leukocyte, as well as decrease the skin microcirculatory perfusion value. PTX can inhibit the aggrega- tion and adhesion of platelets and leukocytes through increasing the content of PG12 and decreasing contents of other factors mentioned above, thus alleviating the microcircnlatory dysfunction after HEB.