水蛭对糖尿病大鼠视网膜微血管形态的影响

目的：探讨水蛭对糖尿病大鼠视网膜微血管形态的影响，方法：40只SD大鼠随机分成正常对照组，链脲佐菌素糖尿病模型组与水蛭干预组，将水蛭（每天1．67g/kg)混入普通饲料给药，180天后测血液流变指标，血浆一氧化氮（NO）水平，丙二醛（MDA）含量以及全血谷胱甘肽过氧化物酶（GSH－PX），组织型纤溶酶原激活物（t-PA)及纤溶酶原激活抑制剂（PAI）活性等，对视网膜血管铺片进行光镜及透射电镜观察。结果：病程6个月的模型组大鼠的血液存在明显的高凝，高粘现象，并出现了周细胞减少，微血管瘤，无细胞毛细血管及影周细胞等早期糖尿病视网膜病变的特征性改变，水蛭干预组视风膜病变与模型组相比明显减轻，结论：水蛭过早期糖尿病大鼠视网膜变具有良好的防治作用。可能与其能减轻氧自由基损伤，提高抗脂质过氧化作用，增强纤溶性及改善血流变学指标有关。

Influence of leech on the morphologic changes of retinal microvessel in diabetic rats

OBJECTIVE To evaluate the influence of leech on the morphologic changes of retinal microvessel in diabetic rats.METHODS Forty male Sprague-Dawley rats were randomly divided into normal control group,streptozotocin(STZ) rats group with diabetic mellitus and diabetic mellitus group treated with leech. The rats with mellitus diabetic were fed with the powder of leech mixed with the food(1.67g/kg each day) in the treated group. At 6 months, blood rheology indexes, level of nitrogen monoxide, content of malondialdehyde(MDA), glutathione peroxides(GSH-PX) in whole blood, tissue plasminogen activator(t-PA) and inhibitor of plasminogen act ivator (PAI) were detected. Retinal digest preparations were observed with light microscope and transmission electronic microscope.RESULTS At six months, there was a obviously coacervation and viscousness status. The retinal digest preparations of the STZ-diabetic rats showed characteristic retinal changes, including decrease of pericytes, microaneurysm, acellular capillary and pericyte ghost, that are some characteristic changes in early diabetic retinopathy. Retinal changes were better in the treated group with leech than that in the model group. CONCLUSION Early treatment with leech may be helpful in delaying or possibly preventing the dibetic retinopathy, and this effect may be partly achieved by decreasing the lesions of oxygen free radical. It could promote activity of anti lipid overoxidation, and plasma t-PA, and PAI. Blood rheology indexes may be better.