重度烧伤休克大鼠L-选择素转录水平表达的研究

Study on the expression of L-selectin at transcription level in severe burn shock rat

目的和方法：２４只ＳＤ大鼠随机分为３组：正常对照组、烧伤１ｈ组、烧伤３ｈ组。用８０℃热水烫伤腰部以下肢体３０ｓ造成深Ⅱ度烧伤，复制大鼠重度烧伤休克模型。采集３组动物外周血，分离提取外周血白细胞总ＲＮＡ，与长臂光敏生物素标记的Ｌ－选择素探针进行点杂交。结果：与正常对照组比，两烧伤组Ｌ－选择素转录均下调，烧伤３ｈ组比烧伤１ｈ组又有下降。结论：休克时Ｌ－选择素转录减少可以减轻游离的白细胞进一步附壁粘着，这可能是休克时机体的自身保护机制之一；Ｌ－选择素转录减少可能造成炎症或感染时白细胞游出的减少，使机体的抵抗力下降。

AIM and METHODS:For investigation of L-selectin expression at transcription level, 24 Sprague Dawley rats were randomly divided into three groups:normal group, 1 and 3 hour after burn group. The rats were burned with 80℃ hot water for 30 seconds to produce severe burn shock model.Total RNA of peripheral leukocytes was extracted and was used to hybridize with photobiotin-labeled L-selectin probe. RESULTS:Transcriptional expression level of L-selectin in burn shock group was much lower than that of normal group, and successive measurments also showed down-regulation tendency. CONCLUSIONS: Transcriptional reduction of L-selectin may alleviate the adhesion of leukocytes to the venule wall, which may be one of the protective mechanism of the body during shock. But down-regulation of L-selectin transcription may also reduce the mumber of leukocytes to the inflammatory sites and affects the body resistance..