顺铂对耳蜗螺旋神经节细胞毒性作用及机制

目的通过透射电镜及免疫组化法观察顺铂对耳蜗螺旋神经节细胞的毒性作用。方法16只豚鼠随机均分为2组。顺铂组连续5天腹腔注射顺铂2mg/kg/d;对照组连续5天腹腔注射生理盐水2mg/kg/d;用药前后测试听力,处死动物后制作耳蜗标本,透射电镜观察及免疫组化法测定诱导型一氧化氮合酶(induciblenitricoxidesynthase,iNOS)的表达。结果ABR:顺铂组听力下降明显,阈值显著升高(P<0.01)。透射电镜观察:顺铂组螺旋神经节细胞的细胞器损伤严重,核变形,线粒体肿胀,大量空泡样变,粗面内质网增多,有髓神经纤维的髓鞘增厚;对照组螺旋神经节细胞核无变形,核仁基本居中,线粒体结构正常。免疫组织化学显示:顺铂组螺旋神经节有iNOS阳性反应显色,灰度值降低,iNOS活性升高,与对照组比较,有显著性差异(P<0.01)。结论顺铂可致耳蜗螺旋神经节细胞损伤并呈iNOS阳性表达,导致听力下降。     

热休克蛋白70在顺铂所致豚鼠耳蜗损伤中的表达以及磷霉素钠的保护作用

目的 通过豚鼠在体实验观寨磷霉素钠对顺铂耳毒性的拮抗作用以及热休克蛋白70在耳蜗中的表达情况。方法豚鼠28只,随机分为4组:正常对照组6只;单独应用磷霉素钠组6只,磷霉素钠500mg/Kg,1日1次肌注;单独应用顺铂组8只,一次性给予顺铂15mg/Kg腹腔注射;磷霉素钠保护组8只,先肌肉注射磷霉素钠500mg/Kg,间隔30min后腹腔注射顺铂15mg/Kg。4天后处死所有动物。给药前和处死前各测听觉脑干诱发电位(ABR)1次。断头后取出听泡,固定、脱钙,常规石蜡包埋、切片。HSP70单克隆抗体免疫组化染色,光镜下观察阳性表达部位,图象处理分析系统测定灰度值。结果 单纯磷霉寨钠组ABR阈值无改变;顺铂组阈值明显升高,幅度达37.1±19.9 dBspl,P<0.001;磷霉素钠保护组阈值仅提高8.1±9.6 dBspl,同对照组相比P>0.05。HSP70表达分布在耳蜗中的Corti氏器、螺旋神经节、血管纹等处,顺铂损伤后Corti氏器和螺旋神经节细胞呈强阳性表达。从灰度值来看对照组、顺铂组与磷霉素钠保护组两两比较差异均有显著性,P<0.01或0.05。结论磷霉橐钠在一定程度上可以拮抗顺铂的耳毒性,减小ABR阈值的提高。顺铂损伤后耳蜗Corti氏器和螺旋神经节细胞HSP70呈强阳性表达,表达量与耳蜗的损伤程度一致。     

HO-1在顺铂诱导豚鼠螺旋神经元损伤中的作用

目的检测血红素加氧酶-1在豚鼠耳蜗螺旋神经节顺铂损伤后的表达变化。方法通过免疫组织化学及Western Blot技术,观察耳蜗螺旋神经元损伤后HO-1在不同组间的表达变化。将32只健康豚鼠随机分为4组,每组8只。A组对照组:按体重以0.9%生理盐水12ml/kg腹腔注射,早晚各一次,持续3天。B组顺铂组:按体重12mg/kg顺铂腹腔注射(IP),早晚各一次,持续3天。C组阿魏酸(FA)+顺铂组:先150mg/kg FA腹腔注射预处理1h,再以12mg/kg顺铂IP,早晚各一次,持续三天。D组FA+锌原卟啉Ⅸ(ZnppⅨ)+顺铂组:同时给予150mg/kg FA+ZnppⅨ15umol/kg IP预处理1h,再以12mg/kg顺铂IP,早晚各一次,持续三天。采用免疫组织化学及Wstern Blot技术检测不同组间螺旋神经元HO-1蛋白表达变化。结果在不同的分组中,HO-1在耳蜗螺旋神经节中表达量不同。空白组中,螺旋神经节组织存在微弱的HO-1表达,其蛋白表达量为0.48±0.07;A组蛋白表达量为0.81±0.07,B组蛋白表达量为0.9±0.05,C组蛋白表达量为0.61±0.07。4个组两两间差异均有统计学意义(p<0.0001)。结论 HO-1在C组中表达量最多,B组次之,D组最少,表明HO-1可能参与顺铂损伤螺旋神经元后的修复过程。     

脑源性神经营养因子基因修饰的骨髓间充质干细胞在药物致聋豚鼠内耳的表达及保护作用

目的 探讨脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)基因修饰的骨髓间充质干细胞(mesenchymal stem cell,MSC)在药物致聋豚鼠内耳的表达及对螺旋神经节细胞(spiral ganglion cell,SGC)的保护作用.方法 阿米卡星致聋的豚鼠随机数字表法分为两组,治疗组经鼓阶开窗注射BDNF基因修饰的MSC,对照组注射外淋巴液.各组分别在术后7 d及28 d处死动物,荧光定量反转录聚合酶链反应(RT-PCR)检测耳蜗组织中BDNF mRNA的表达,耳蜗切片计算SGC细胞密度,末端脱氧核苷酸转移酶介导dUTP缺口末端标记法(terminal deoxynucleotidyl transferase mediated dUTP nick end labeling,TUNEL)检测SGC凋亡情况.结果 治疗组在术后7 d和28 d的BDNF mRNA相对表达量均明显高于对照组,差异具有统计学意义(P值均＜0.01).治疗组术后7 d及28 d的SGC密度均高于对照组,并且治疗组术后7 d及28 d的SGC凋亡指数也比对照组明显下降,差异具有统计学意义(P值均＜0.01).结论 BDNF基因修饰的MSC在致聋豚鼠内耳中的表达时间超过28 d,对SGC具有保护作用.     

豚鼠螺旋神经节细胞中钙磷脂结合蛋白Ⅵ表达及意义

目的钙离子在耳蜗功能中具有重要作用。本实验探讨与钙离子结合蛋白相关annexin家族中重要成员annexinⅥ在螺旋神经节细胞中的表达和意义。方法用原位杂交的方法检测正常和经过倍频窄带噪声刺激6小时的豚鼠基底膜铺片和石蜡包埋中轴切片中annexinⅥmRNA表达,所选用的探针为经过FITC标记的寡核苷酸。结果在正常未经处理的和接受噪声刺激的豚鼠耳蜗螺旋神经节细胞中均可见annexinⅥmRNA表达。接受噪声刺激的豚鼠耳蜗螺旋神经节细胞的染色明显较正常豚鼠强烈。结论annexinⅥ参于内耳的生理活动,短期的噪声刺激后annexinⅥ在螺旋神经节细胞中表达增高。     

脑源性神经营养因子对耳蜗螺旋神经节的保护作用

目的　观察腺病毒携带的脑源性神经营养因子 (brainderivedneurotrophicfactor,BDNF)在豚鼠耳蜗中的表达 ,及噪声损伤后对螺旋神经节的保护作用。方法　 2 7只白色纯种豚鼠 ,暴露于135dBSPL ,4kHz的窄带噪声 4h。 7d后 ,12只经圆窗注入腺病毒携带BDNF(adenoviral mediatedBDNF ,ad BDNF) ,12只经圆窗注入ad LacZ ,3只注入人工外淋巴液。分别于 1、4、8周后取材 ,石蜡包埋中轴切片后 ,用免疫组化方法 (ABC法 )检测BDNF的表达。于光镜下计数螺旋神经节细胞。结果　在耳蜗各回中BDNF均有表达 ,4、8周组动物较 1周组动物表达弱。在 8周 ,注入ad BDNF组较ad LacZ组和人工外淋巴组螺旋神经节发生退行性病变的数目少 ,螺旋神经节细胞计数结果经统计学t检验 ,P <0 0 1,差异有显著性。结论　腺病毒携带的神经营养因子在耳蜗中能高效表达 ,在噪声损伤情况下腺病毒携带的脑源性神经营养因子对螺旋神经节有保护作用。该研究为基因治疗感音神经性聋提供了坚实的实验基础     

豚鼠耳蜗一氧化氮合酶异型体的定位

目的研究一氧化氮合酶(NOS)的异型体在豚鼠耳蜗的定位分布,以探讨一氧化氮(NO)在内耳听觉生理和病理生理机制中的作用。方法使用特异性NOS异型体抗体,采用ABC免疫组化染色法,观察NOS异型体在正常豚鼠耳蜗的定位表达。结果NOS Ⅰ主要分布在内骨膜、螺旋神经节的核周体、螺旋韧带和Corti's器的细胞。NOSⅢ是耳蜗的主要NOS异型体免疫染色,其主要免疫染色分布于耳蜗神经、螺旋神经节核周体、螺旋韧带和耳蜗毛细血管球的内皮细胞,也见于Corti's器的细胞和神经纤维。NOS Ⅱ在正常豚鼠耳蜗内不表达。 结论结构型NOS(cNOS)表达在耳蜗的多个部位,表明NO参与内耳的正常生理功能,包括神经突触的神经传导、耳蜗血流的调节和耳蜗的骨代谢。     

豚鼠耳蜗一氧化氮合酶异型体的定位

目的 研究一氧化氮合酶(NOS)的异型体在豚鼠耳蜗的定位分布，以探讨一氧化氮(NO)在内耳听觉生理和病理生理机制中的作用。方法 使用特异性NOS异型体抗体，采用ABC免疫组化染色法，观察NOS异型体在正常豚鼠耳蜗的定位表达。结果 NOS Ⅰ主要分布在内骨膜、螺旋神经节的核周体、螺旋韧带和Corti’s器的细胞。NOS Ⅲ是耳蜗的主要NOS异型体免疫染色，其主要免疫染色分布于耳蜗神经、螺旋神经节核周体、螺旋韧带和耳蜗毛细血管球的内皮细胞，也见于Corti’s器的细胞和神经纤维。NOS Ⅱ在正常豚鼠耳蜗内不表达。结论 结构型NOS(cNOS)表达在耳蜗的多个部位，表明NO参与内耳的正常生理功能，包括神经突触的神经传导、耳蜗血流的调节和耳蜗的骨代谢。     

正常和膜迷路积水豚鼠内耳水通道蛋白的表达及意义

目的检测正常和膜迷路积水豚鼠内耳水通道蛋白（aquaporins,AQPs）的表达,探讨其机理和意义。方法 20只健康豚鼠随机分为实验组和对照组,每组10只,实验组（膜迷路积水模型组）豚鼠腹腔注射醋酸去氨加压素,4μg&#183;kg-1&#183;d-1,共1周,诱导其内耳膜迷路积水,对照组豚鼠腹腔注射等量生理盐水。用免疫组化方法检测两组豚鼠内耳水通道蛋白的表达,并进行比较。结果对照组豚鼠内耳中有AQP0、1、2、3、5、7、8的表达,其中AQP0仅在血管纹和螺旋神经节细胞有较弱的表达;AQP1分布于包绕骨迷路、内淋巴囊、内淋巴管的纤维细胞,基底膜鼓阶面细胞、螺旋韧带纤维细胞、螺旋缘纤维细胞、Corti’s器、内外螺旋沟、血管纹、椭圆囊壁、球囊壁、螺旋神经节等;AQP2表达在血管纹、Corti’s器、螺旋神经节细胞和内淋巴囊中;AQP3、7、8三者的分布类似,在螺旋神经节和包绕膜迷路的组织中表达,包括Corti’s器、内外螺旋沟、血管纹、螺旋韧带纤维细胞、螺旋缘、椭圆囊壁、球囊壁、内淋巴囊等;AQP5则表达在Corti’s器、内外螺旋沟、螺旋神经节、螺旋韧带纤维细胞。实验组豚鼠内耳中,血管纹AQP2的表达与对照组较正常豚鼠表达增加,其它亚型AQPs的表达与对照组无明显差异。结论正常豚鼠内耳中有多种AQPs表达,膜迷路积水后豚鼠内耳中AQP2的表达增强,提示膜迷路积水可能与AQP2表达上调有关。     

诱生型一氧化氮合酶在顺铂所致豚鼠耳蜗损伤中的表达

目的：检测诱生型一氧化氮合酶（iNOS）在顺铂所致豚鼠耳蜗损伤中的表达。方法：实验组豚鼠腹腔注射顺铂造成耳蜗损伤，对照组豚鼠腹腔注射等量生理盐水。用免疫组织化学的方法检测iNOS在耳蜗中的表达。结果：iNOS在实验组耳蜗的表达呈阳性，在对照组耳蜗的表达呈阴性。结论：iNOS在顺铂损伤耳蜗中呈阳性表达，iNOS催化产生大量NO而致耳蜗损伤。     

Intracochlear administration of thiourea protects against cisplatin-induced outer hair cell loss in the guinea pig

Amelioration of cisplatin-induced side-effects is of great clinical importance. Local administration of a cytoprotective agent to the inner ear offers a possibility to prevent cisplatin-induced ototoxicity without risk of interference with the antitumour effect. The ideal substance for local administration has yet to be identified. Thiourea (TU) has unique properties that make it an interesting candidate. This study was initiated to test the hypothesis that TU given by local administration protects against cisplatin ototoxicity in the guinea pig. After baseline auditory brainstem response (ABR) assessment, the left cochlea was implanted with a microtip catheter connected to an osmotic pump filled with either 27 mg/ml TU in artificial perilymph (AP), or AP administered for the full duration of the study. Three days post-implant, animals with normal ABRs received an intravenous injection of 8 mg/kg body-weight cisplatin. Five days after the cisplatin treatment ABRs were reassessed, animals decapitated and bilateral cytocochleograms prepared. TU-treated ears demonstrated significantly lower outer hair cell (OHC) loss as compared to contralateral untreated ears, and significantly lower OHC loss compared to AP-treated ears. ABR threshold shift did not differ significantly between the two groups. It can be postulated that TU demonstrates partial protection against cisplatin-induced ototoxicity.     

小鼠耳蜗血管纹Na-K-2Cl联合转运子1在顺铂耳毒性发生时的改变

目的研究顺铂(cis-dichlorodiammine platinum,Cisplatin)耳毒性发生后耳蜗血管纹Na-K-2Cl联合转运子1(NKCC1)的表达情况,并初步探讨其机制。方法选取健康CBA/CaJ小鼠20只,随机分为对照组和实验组各10只,实验组动物连续腹腔注射顺铂3.5mg.kg-1.d-1,建立顺铂耳毒性小鼠模型,对照组注射等量生理盐水。以听性脑干反应(ABR)阈值作为评价听功能的指标,检测给药前后小鼠听功能的改变,并采用免疫组织化学(SP法)结合免疫荧光实验技术,观察对照组和实验组小鼠腹腔注射顺铂前后耳蜗血管纹NKCC1表达的变化。结果NKCC1在小鼠耳蜗血管纹主要表达于边缘细胞,而顺铂作用后血管纹边缘细胞的NKCC1表达明显减弱,图像分析显示两组平均灰度值差异有显著统计学意义(P<0.01)。结论小鼠顺铂耳毒性作用后血管纹边缘细胞NKCC1的表达量明显减弱,这可能是顺铂耳毒性发生机制中的一个重要环节。     

The effect of intratympanic vitamin C administration on cisplatin-induced ototoxicity

The Objective of this study is to investigate the effect of intratympanic injection of vitamin C on cisplatin-induced ototoxicity. The study included 24 albino adult female rats (48 ears). The study animals were divided into four groups each of which was composed of six animals including a control (intraperitoneal cisplatin), a cisplatin–saline (saline intratympanic + intraperitoneal cisplatin), a C vit (intratympanic vitamin C) and a cisplatin–C vit group (intraperitoneal cisplatin + intratympanic vitamin C). As two animals had died due to cisplatin-induced ototoxicity (one in the control and one in the cisplatin-saline group) they were excluded from the study. The experiment was terminated, performing distortion product otoacoustic emission (DPOAE) measurement prior to procedures and at the end of the experiment. The results of the statistical analysis were evaluated. In the cisplatin–C vit group, there were no significant decreases in DPOAE amplitudes at 2 kHz (p > 0.05). Although a decrease was observed in DPOAE amplitudes at 2.8, 4, 6, and 8 kHz frequencies, these amplitude reductions were significantly lower than the control group (p < 0.05). Intratympanic vit C infusion provided a protective effect against cisplatin-induced ototoxicity primarily at 2 kHz and at other frequencies (2.8, 4, 6, and 8 kHz), and it did not produce a toxic effect in the cochlea.     

脑活素拮抗豚鼠庆大霉素耳毒性机理的研究

目的探讨脑活素拮抗豚鼠庆大霉素耳毒性作用机理。方法取听力正常豚鼠60只,随机分为4组,每组15只A组(脑活素组),肌肉注射脑活素360mg·kg-1·d-1;B组(庆大霉素组),肌肉注射庆大霉素120mg·kg-1·d-1;C组(庆大霉素 脑活素组),肌肉注射庆大霉素 脑活素,剂量同上;D组(生理盐水组),肌肉注射等量生理盐水。各组均连续用药10d再饲养一周,第17d处死,取左侧听泡,进行琥珀酸脱氢酶化学组织染色观察其活性;取右侧听泡行石蜡包埋切片,在光镜下进行螺旋神经节细胞计数,免疫组织化学SP法检测脑源性神经生长因子(brain-derivedneurotrophicfactor,BDNF)在耳蜗中的表达。结果庆大霉素 脑活素组螺旋神经节细胞退行性病变数目明显低于庆大霉素组,神经纤维变性明显较少,琥珀酸脱氢酶活性明显增高,BDNF在耳蜗中呈阳性表达。结论脑活素对庆大霉素所致耳毒性有明显保护作用,其机理在于脑活素能拮抗庆大霉素对毛细胞有氧代谢的抑制,与BDNF对螺旋神经元的营养修复作用有关。     

Effect of high-dose cisplatin on auditory brainstem responses and otoacoustic emissions in laboratory animals

OBJECTIVE: The role of transient evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE) as early indicators of cisplatin-induced ototoxicity in three different rodent species--the guinea pig. the albino rat, and the fat sand rat (Psammomys obesus)--was investigated. In addition, an attempt was made to determine which of the three rodent species is most susceptible to cisplatin-induced ototoxicity as measured by auditory brainstem responses (ABR), BACKGROUND: There have been numerous clinical and experimental reports on cisplatin-induced ototoxicity, but to the authors' best knowledge, there has been no comparative report on the short-term effects of cisplatin on OAE measured with commercially available equipment between different rodent species. METHODS: Cisplatin was systemically administered as a single high dose (12 mg/kg intraperitoneally) to all three species, and the ototoxic effects were measured before and 3 days after the injection of cisplatin in the same animals, using ABR, TEOAE, and DPOAE. RESULTS: The ABR thresholds were significantly elevated in the guinea pigs and the albino rats but not in the sand rats. Significant depression of TEOAE energy and DPOAE amplitude occurred only in the guinea pigs. The depression of the DPOAE was greater than that of the TEOAE. The guinea pigs showed the greatest degree of ototoxicity (depression of ABR and OAE). CONCLUSIONS: Among the three rodent species, the guinea pig has the potential to be used as a sensitive animal model in studies of cisplatin ototoxicity. The study also showed that the recordings of TEOAE and DPOAE, in addition to ABR, are sensitive techniques for the assessment of cisplatin-induced ototoxicity.     

Protective Effect of Minocycline Against Cisplatin-induced Ototoxicity

Objectives

Cisplatin, a widely used chemotherapeutic agent, has serious side effects, including nephrotoxicity and ototoxicity. Minocycline is a semisynthetic second-generation tetracycline that exerts anti-inflammatory and neuroprotective effects. The purpose of this study was to elucidate the protective effect of minocycline against cisplatin-induced ototoxicity in the auditory hair cell.

Methods

The House Ear Institute-Organ of Corti 1 (HEI-OC1) cell line and guinea pigs were used for in vitro and in vivo experiments. Cells were exposed to cisplatin with or without pre-treatment with minocycline. Cell survival was analyzed using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide). Whole-cell lysates were collected and immunoblotted with antibodies against Bcl-2, p-c-Jun, active caspase-3, cleaved poly (ADP-ribose) polymerase (PARP), and apoptosis-inducing factor (AIF). The guinea pigs received intraperitoneal injections of cisplatin alone or following minocycline pretreatment. The auditory brainstem response was tested and the cochleae were harvested and evaluated using scanning electron microscopy.

Results

Survival significantly increased in cells pretreated with minocycline compared with cells exposed to cisplatin alone. Cisplatin treatment increased the expression of active caspase 3, p-c Jun, PARP, and AIF, and pretreatment with minocycline attenuated this response. In animal study, the threshold shift by cisplatin injection in the auditory brainstem response was less pronounced in animals pretreated with minocycline. Scanning electron microscopy revealed more severe damage to the outer hair cells at the basal and middle turns than the apical turn.

Conclusion

Minocycline partially protects against cisplatin-induced ototoxicity via both caspase-dependent and independent apoptosis pathways.     

Application of antioxidants and other agents to prevent cisplatin ototoxicity

OBJECTIVE/HYPOTHESIS: To review the recent data from experiments performed in this laboratory to test the hypothesis that cisplatin ototoxicity is related to depletion of glutathione and antioxidant enzymes in the cochlea and that the use of antioxidants or protective agents would protect the cochlea against cisplatin damage and prevent hearing loss. STUDY DESIGN/METHODS: Data were reviewed from experiments performed in this laboratory. Control rats were treated intraperitoneally with cisplatin 16 mg/kg. Experimental rats were given cisplatin in combination with one of the following protective agents: diethyldithiocarbamate, 4-methylthiobenzoic acid, ebselen, or lipoic acid. Animals in each group underwent auditory brainstem response (ABR) threshold testing before and 3 days after treatment. Cochleae were removed after final ABR testing and analyzed for glutathione and activities of the enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and malondialdehyde. RESULTS: Rats in the control group receiving cisplatin were found to have significant ABR threshold shifts. This was accompanied by a reduction of glutathione and the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase, and glutathione reductase) and an elevation of malondialdehyde. Experimental animals had preservation of ABR thresholds and levels of glutathione, antioxidant enzyme activity, and malondialdehyde that were similar to untreated animals. CONCLUSION: Cisplatin ototoxicity appears to be initiated by fee-radical production, which causes depletion of glutathione and antioxidant enzymes in the cochlea, and lipid peroxidation, manifested by an increase in malondialdehyde. These effects were blocked by each of a series of antioxidant compounds given in combination with cisplatin. A mechanism for cisplatin ototoxicity is elaborated with a proposed plan of chemoprevention using agents with different mechanisms of action. These substances could be used alone or in combination to reduce the severity of cisplatin ototoxicity in patients.     

Early Physiological and Cellular Indicators of Cisplatin-Induced Ototoxicity

Cisplatin chemotherapy often causes permanent hearing loss, which leads to a multifaceted decrease in quality of life. Identification of early cisplatin-induced cochlear damage would greatly improve clinical diagnosis and provide potential drug targets to prevent cisplatin’s ototoxicity. With improved functional and immunocytochemical assays, a recent seminal discovery revealed that synaptic loss between inner hair cells and spiral ganglion neurons is a major form of early cochlear damage induced by noise exposure or aging. This breakthrough discovery prompted the current study to determine early functional, cellular, and molecular changes for cisplatin-induced hearing loss, in part to determine if synapse injury is caused by cisplatin exposure. Cisplatin was delivered in one to three treatment cycles to both male and female mice. After the cisplatin treatment of three cycles, threshold shift was observed across frequencies tested like previous studies. After the treatment of two cycles, beside loss of outer hair cells and an increase in high-frequency hearing thresholds, a significant latency delay of auditory brainstem response wave 1 was observed, including at a frequency region where there were no changes in hearing thresholds. The wave 1 latency delay was detected as early cisplatin-induced ototoxicity after only one cycle of treatment, in which no significant threshold shift was found. In the same mice, mitochondrial loss in the base of the cochlea and declining mitochondrial morphometric health were observed. Thus, we have identified early spiral ganglion-associated functional and cellular changes after cisplatin treatment that precede significant threshold shift.     

硫普罗宁对顺铂所致耳毒性的保护作用

目的探讨硫普罗宁对顺铂耳毒性的保护作用。方法将48只豚鼠随机等分为四组,每组12只:生理盐水对照组:生理盐水腹腔注射2ml/d共7天;硫普罗宁组:腹腔注射硫普罗宁0.3g·kg-1·d-1共7天;顺铂组:腹腔注射顺铂4mg·kg-1·d-1共4天;顺铂加硫普罗宁组:先腹腔注射硫普罗宁0.3g·kg-1·d-13天,从第4天起先腹腔注射硫普罗宁0.3g·kg-1·d-1,再腹腔注射顺铂4mg·kg-1·d-1共4天。动物用药前后行听性脑干反应检查。每组半数动物做耳蜗基底膜铺片硝酸银染色,在光镜下观察毛细胞形态,半数动物取耳蜗组织匀浆测局部丙二醛(malonaldehyde,MDA)和超氧化物歧化酶(superoxide dismutase,SOD)的含量。结果顺铂应用后可使(auditory brainstem response,ABR)反应阈上升,波I潜伏期延长,耳蜗组织匀浆内MDA含量增多,SOD活性下降,与生理盐水对照组相比差异具有显著统计学意义(P<0.01)。硫普罗宁可改善顺铂的耳毒性,使ABR反应阈下降,波I潜伏期缩短,局部MDA含量减少,SOD活性提高,与顺铂组相比差异具有显著统计学意义(P<0.05)。光镜下见应用顺铂后外毛细胞明显损伤,而硫普罗宁可减轻上述损伤。结论硫普罗宁可能通过抗自由基原理来改善顺铂的耳毒性。