大鼠肾脏热缺血再灌注损伤过程中水通道蛋白的表达变化

背景:如何有效防治肾脏的缺血再灌注损伤,一直是肾损伤与肾移植过程中众多学者研究的热点,但目前仍然不是很清楚相关实验表明水通道蛋白在这一过程中起重要作用.目的:研究大鼠肾脏缺血再灌注损伤后水通道蛋白1的表达变化与肾功能变化的关系.设计、时间及地点:随机对照动物实验,于2007-06/2008-02在大连医科大学组织胚胎实验室完成.材料:健康成年雌性Wister大鼠80只,随机分为对照组和缺血再灌注组,每组又分为术后1,2,3,5,7 d 5个时间点组,8只/组,建立大鼠左侧肾脏缺血再灌注损伤模型.方法:所有大鼠均摘除右肾,游离左侧肾蒂,缺血再灌注组大鼠用无损伤动脉夹夹闭左侧肾蒂,阻断出入肾脏血流,40 min后重新恢复肾脏血液灌注.当松开动脉夹后肾脏在2～5 min内颜色由暗红转为鲜红表明缺血再灌注损伤模型建立成功,肾血管无血栓形成,关腹.若超过5 min肾脏颜色仍然未转为鲜红色则认为肾脏有血栓形成,排除出缺血再灌注组,不进行夹闭,40 min后关腹.主要观察指标:于缺血再灌注损伤1,2,3,5,7 d处死大鼠,留取尿液、血清、肾脏标本行尿常规、肾功能、肾脏病理形态学及水通道蛋白-1的免疫组化、RT-PCR检测.结果:大鼠肾脏缺血再灌注损伤后出现尿量增多、尿渗透压降低,血肌苷、尿素氮升高症状;苏木精-伊红染色示肾小管上皮细胞肿胀、坏死、脱落;水通道蛋白表达量及其mRNA含量均较对照组减少,这些变化于缺血再灌注损伤 1 d时最低,至缺血再灌注损伤 5 d时恢复正常.结论:肾脏缺血再灌注损伤后水通道蛋白表达的减少可能是急性肾衰竭时反映肾功能变化的重要指标之一.

Expression changes of aquaporin during ischemic reperfusion injury to rat kidney

BACKGROUND: It is a hot investigation to many scholars that how to cure and prevent renal ischemic reperfusion injury in a utility way, but the mechanism is unclear at present. The investigation indicates that aquaporiin-1 plays an important role during this process. OBJECTIVE: To research the correlation between aquaporin-1 expression and renal function change following renal ischemic reperfusion injury. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at Histology and Embryology Laboratory of Dalian Medical University from June 2007 to December 2008. MATERIALS: A total of 80 healthy female adult Wister rats were randomly divided into control group and ischemia-reperfusion group. Rats in each group were observed at days 1, 2, 3, 5, and 7 after operation, with 8 rats for each group. The ischemia-reperfusion injury was established on the left kidney. METHODS: Right kidney was removed. The left renal pedicle was freed and occlused to establish ischemia-reperfusion injury model. After 40 minutes, the blood was re-flowed. If the kidney colored from dark red to bright red within 2-5 minutes, the ischemia-reperfusion injury models were successfully established, and the thrombus was not formed in the kidney vessels. If the kidney was still dark red after 5 minutes, the thrombus was formed, and the rats were excluded from the ischemia-reperfusion group. The abdomen was sutured after 40 minutes.MAIN OUTCOME MEASURES: Rats were sacrificed at days 1, 2, 3, 5, and 7 after ischemia-reperfusion injury. Samples of urine, serum, and kidney were performed with the examinations of urine, renal function, renal pathology and morphology, immunohistological assay of aquaporiin-1, and RT-PCR assay. RESULTS: After ischemia-reperfusion injury, the rats had hydrouria, urine osmotic pressure depress, symptoms of carnine and urea nitrogen increasing. HE staining demonstrated that renal tubular epithelial cells were swelling, necrosis, and desquamate. Aquaporin-1 expression and its mRNA level was decreased; in particular, the expression and level were the lowest at day 1 after ischemia-reperfusion injury and recovered to normal value at day 5 after ischemia-reperfusion injury. CONCLUNSION: The down expression of aquaporin-1 maybe one of the important indicators to reflect renal functional changes of acute renal failure following renal ischemia-reperfusion injury.