低分子量肝素对DSS诱导小鼠结肠炎的疗效观察

目的　评价低分子量肝素预防及治疗 DSS结肠炎小鼠的有效性。方法　 2 0只正常小鼠随机分成两组 ,饮用 DSS 7d,预防组皮下注射低分子量肝素 ,对照组皮下注射生理盐水。另取 2 0只 DSS诱导的结肠炎小鼠随机分成两组 ,治疗组皮下注射低分子量肝素 ,对照组皮下注射生理盐水 7d。用疾病活动指数 (DAI)、组织学评分和MSB纤维素染色检测微血栓以评价疗效。结果　低分子量肝素预防组与对照组的 DAI、直肠、横结肠组织学评分分别为 2 .4 0、2 .5 2 (P>0 .0 5 ) ,1.6 5、1.85 (P>0 .0 5 ) ,1.5 5、1.72 (P>0 .0 5 )。低分子量肝素在预防组降低微血栓的形成 ,对照组 10例有 6例微血栓阳性 ,预防组 1例阳性 ,P=0 .0 2 9。低分子量肝素治疗组与对照组的 DAI、直肠、横结肠组织学评分分别为 0 .4 2、0 .4 4 (P>0 .0 5 ) ,1.36、1.75 (P<0 .0 5 ) ,1.30、1.6 5 (P<0 .0 5 )。对照组 10例有 3例微血栓阳性 ,治疗组 1例阳性 ,P=0 .2 91。结论　低分子量肝素可预防 DSS结肠炎小鼠微血栓形成和抑制结肠炎症 ,提示低分子量肝素用于难治性溃疡性结肠炎治疗也可能有效

The Preventive and Therapeutic Effects of Low Molecular Weight Heparin on DSS-induced Colitis in Mice

Objective To evaluate the preventive and therapeutic effects of low molecular weight heparin(LMWH) on dextran sulphate sodium (DSS) induced colitis in mice. Methods Twenty normal mice were randomized into two groups: 10 mice of the prevention group received DSS per os and LMWH by sub cutaneous injection for 7 days; 10 mice as controls received DSS per os and sub cutaneous normal saline for 7 days. Another 20 mice with DSS induced colitis were randomized into two groups: the treatment group received sub cutaneous injection of LMWH and the control group received subcutaneous injection of normal saline for 7 days. The preventive and therapeutic effects of LMWH were assessed by disease activity index (DAI), histologic score and MSB fibrin staining to identify microvascular thrombus. Results The DAI, rectal and transverse histological scores of the prevention group compared with those of the control group were 2.40 vs 2.52 ( P >0.05), 1.65 vs 1 85 ( P >0.05),1.55 vs 1.72 ( P >0.05), respectively. Microvascular thrombi in the prevention group decrease significantly as compared with the control; microvascular thrombi were positive in 6 of 10 controls, but only one was positive in the prevention group, P =0.029. The DAI, rectal and transverse histological scores in the treatment group compared with those of the control were 0.42 vs 0.44 ( P >0.05), 1.36 vs 1.75( P <0.05), 1.30 vs 1.65( P <0.05), respectively. Microvascular thrombi were positive in 3 of 10 controls, and one microvascular thromous was positive in the treatment group, P =0.291. Conclusion LMWH could effectively prevent microvascular thrombosis and inhibit colonic and rectal inflammation in the mice with DSS induced colitis. These animal experimental results suggested that LMWH might also be used effectively in ulcerative colitis.