Abstract：Objective To investigate the protective effect of calcium dobesilate on tobramycin-induced nephrotoxicity.Methods Thirty male Sprague-Dawley rats were randomly divided into three groups.The control group were injected with the normal saline (3 mL·kg-1·d-1) for 7 d.The model were injected with tobramycin (140 mg·kg-1·d-1) for 7 d.The prevention group were injected with tobramycin (140 mg·kg-1·d-1) plus received calcium dobesilate (100 mg·kg-1·d-1) for 7 d.N-acetyl-β-D-glucosaminidase (NAG) , serum creatinine (SCr) and blood urea nitrogen (BUN) concentrations were monitored.Superoxide dismutase (SOD) and malondialdehyde (MDA) were measured to assess the level of oxidative stress in renal tissue samples.Results The urinary NAG, SCr, BUN and MDA levels were significantly higher in the model group and the prevention group than that in the control group, and the SOD level of the renal cortex homogenate was significantly lower than that in the control group (P<0.05) .The urinary NAG, SCr, BUN and MDA levels were significantly lower in the prevention group than that in the model group, and the level of SOD of the renal cortex homogenate was significantly higher than in the model group (P<0.05) .Conclusion Calcium dobesilate is capable of protecting rats against tobramycin-induced nephrotoxicity.

　　Keyword：kidney diseases; tobramycin; calcium dobesilate;

　　妥布霉素是第二代氨基糖苷类抗生素, 在FDA批准的氨基糖苷类抗生素中与庆大霉素、丁胺卡那霉素等是临床上常见的处方[1], 用于治疗感染革兰阴性菌引起的疾病, 包括铜绿假单胞菌引起的呼吸道感染[2], 目前常用于囊性纤维化疾病的治疗[3-4]。妥布霉素是一种剂量依赖性抗生素, 在体内不代谢, 经过肾脏清除, 接受妥布霉素治疗超过7d的患者中, 高达22%患者会出现肾毒性风险[5]。肾毒性是氨基糖苷类抗生素的不良反应之一, 临床表现为血清肌酐 (serum creatinine, SCr) 和尿素氮 (blood usea nitrogen, BUN) 水平升高[4]。研究表明, 抗氧化剂的消耗降低了氨基糖苷类抗生素引起肾毒性的可能性[6-7]。羟苯磺酸钙是一种强抗氧化剂, 可以清除氧自由基, 并能够有效预防因妥布霉素刺激活性氧物质 (reactive oxygen species, ROS) 而引起的机体氧化应激, 从而达到保护肾脏的作用。本研究旨在探讨羟苯磺酸钙对妥布霉素诱导的肾毒性的预防保护作用, 报告如下。

　　1、材料与方法

　　1.1、实验动物及材料

　　雄性SD大白鼠30只, 普通级, 8周龄, 体重210~230g。硫酸妥布霉素注射液 (上海禾丰制药有限公司) 80mg, 2mL;羟苯磺酸钙胶囊 (西安利君制药有限责任公司) 0.5g。
　　1.2、动物分组及动物模型的建立

　　采用随机数字表法将30只健康清洁雄性SD大鼠分为对照组、模型组、预防组 (n=10) 。对照组腹腔注射生理盐水3mL·kg-1·d-1, 共7d;模型组腹腔注射妥布霉素140mg·kg-1·d-1, 共7d;预防组腹腔注射妥布霉素140mg·kg-1·d-1加羟苯磺酸钙100mg/kg灌胃, 共7d。

　　1.3、取材与方法

　　各组动物在实验前取尿留样, 并在第7天注射和灌胃结束后, 分别放入代谢笼中留24h取尿, 测尿N-乙酰-D-氨基葡萄糖苷 (N-acetyl-β-D-glucosaminidase, NAG) 水平, 实验大鼠在第8天取尾静脉血样检测SCr和BUN, 然后麻醉处死大鼠, 取右肾制成10%肾皮质匀浆, 测定超氧化物歧化酶 (superoxide dismutase, SOD) 和丙二醛 (malondialdehyde, MDA) , 取左肾固定在10%甲醛中, 制成石蜡切片进行光镜检查。指标测定方法:尿NAG测定使用N-乙酰-β-D-氨基葡萄糖苷酶检测试剂盒 (比色法) ;SCr测定使用血清肌酐测定试剂盒 (酶终点法) ;BUN测定使用尿素氮测定试剂盒 (酶法) ;SOD活性变化使用超氧化物歧化酶测定试剂盒 (比色法) ;MDA测定使用丙二醛含量检测试剂盒 (比色法) ;肾组织形态学检查, 制成石蜡切片后, 分别进行HE、PAS染色, 光学显微镜检查。

　　1.4、统计学方法

　　应用SPSS 19.0统计学软件分析数据。计量资料比较采用单因素方差分析和LSD-t检验。P<0.05为差异有统计学意义。

　　2、结果

　　2.1、各组大鼠尿NAG、SCr、BUN水平比较

　　模型组和预防组大鼠尿NAG、SCr、BUN水平显着高于对照组, 预防组大鼠尿NAG、SCr、BUN水平显着低于模型组, 差异均有统计学意义 (P<0.05) , 见表1。
表1 各组大鼠尿NAG, SCr、BUN水平比较