目的:观察肾虚对豚鼠耳蜗血管纹毛细血管及听功能的影响,为进一步研究中医"肾开窍于耳"的理论以及阐明肾虚致聋机制提供实验基础。方法:筛选健康活泼、耳廓反射灵敏的白色红目豚鼠40只,随机分成肾虚模型组和正常对照组,利用...目的:观察肾虚对豚鼠耳蜗血管纹毛细血管及听功能的影响,为进一步研究中医"肾开窍于耳"的理论以及阐明肾虚致聋机制提供实验基础。方法:筛选健康活泼、耳廓反射灵敏的白色红目豚鼠40只,随机分成肾虚模型组和正常对照组,利用糖皮质激素制备豚鼠"肾虚"模型,造模完成后测试各组豚鼠ABR阈值以及90 dB SPL给声强度下Ⅲ波潜伏期。断头处死豚鼠,取出各组听泡,苏木素伊红染色后进行血管纹铺片,显微镜下观察血管纹毛细血管病理改变及计算各组铺片的血管纹毛细血管面积与视野面积的比值。结果:(1)造模后肾虚模型组豚鼠ABR阈值显著提高,且90 dB SPL给声强度下Ⅲ波潜伏期明显延后,两者与正常对照组相比有显著性差异(P<0.01);(2)肾虚模型组豚鼠耳蜗血管纹毛细血管出现断流或红细胞淤积现象,且其毛细血管面积比值明显小于对照组,统计结果显示两者相比有显著性差异(P<0.05)。结论:肾虚可引起耳蜗血管纹毛细血管面积比值降低、血管收缩,出现断流或红细胞淤积现象,有可能是造成听功能减退的原因之一。展开更多
It is well known that ethacrynic acid (EA) can potentiate the ototoxicity of aminoglycoside antibiotics (AmAn) such as kanamycin (KM),if they were applied at the same time.Currently,to create the model of EA-KMinduced...It is well known that ethacrynic acid (EA) can potentiate the ototoxicity of aminoglycoside antibiotics (AmAn) such as kanamycin (KM),if they were applied at the same time.Currently,to create the model of EA-KMinduced cochlear lesion in rats,adult rats received a single injection of EA (75 mg/kg,intravenous injection),or followed immediately by KM (500 mg/kg,intramuscular injection).The hearing function was assessed by auditory brainstem response (ABR) measurement in response to click and/or tone bursts at 4,8,12,16,20,24,and 32 kHz.The static microcirculation status in the stria vascularis after a single EA injection was evaluated with eosin staining.The pathological changes in cochlear and vestibular hair cells were also quantified after co-administration of EA and KM.After a single EA injection,blood flow in vessels supplying the stria vascularis rapidly diminished.However,the blood supply to the cochlear lateral wall partially recovered 5 h after EA treatment.Threshold changes in ABR were basically parallel to the microcirculation changes in stria vascularis after single EA treatment.Importantly,disposable co-administration of EA and KM resulted in a permanent hearing loss and severe damage to the cochlear hair cells,but spared the vestibular hair cells.Since the cochlear lateral wall is the important part of the blood-cochlea barrier,EA-induced anoxic damage to the epithelium of stria vascularis may enhance the entry of KM to the cochlea.Thus,experimental animal model of selective cochlear damage with normal vestibular systems can be reliably created through co-administration of EA and KM.展开更多
文摘目的:观察肾虚对豚鼠耳蜗血管纹毛细血管及听功能的影响,为进一步研究中医"肾开窍于耳"的理论以及阐明肾虚致聋机制提供实验基础。方法:筛选健康活泼、耳廓反射灵敏的白色红目豚鼠40只,随机分成肾虚模型组和正常对照组,利用糖皮质激素制备豚鼠"肾虚"模型,造模完成后测试各组豚鼠ABR阈值以及90 dB SPL给声强度下Ⅲ波潜伏期。断头处死豚鼠,取出各组听泡,苏木素伊红染色后进行血管纹铺片,显微镜下观察血管纹毛细血管病理改变及计算各组铺片的血管纹毛细血管面积与视野面积的比值。结果:(1)造模后肾虚模型组豚鼠ABR阈值显著提高,且90 dB SPL给声强度下Ⅲ波潜伏期明显延后,两者与正常对照组相比有显著性差异(P<0.01);(2)肾虚模型组豚鼠耳蜗血管纹毛细血管出现断流或红细胞淤积现象,且其毛细血管面积比值明显小于对照组,统计结果显示两者相比有显著性差异(P<0.05)。结论:肾虚可引起耳蜗血管纹毛细血管面积比值降低、血管收缩,出现断流或红细胞淤积现象,有可能是造成听功能减退的原因之一。
基金Project (No. R01 DC006630) supported by the National Institutes of Health (NIH) of USA
文摘It is well known that ethacrynic acid (EA) can potentiate the ototoxicity of aminoglycoside antibiotics (AmAn) such as kanamycin (KM),if they were applied at the same time.Currently,to create the model of EA-KMinduced cochlear lesion in rats,adult rats received a single injection of EA (75 mg/kg,intravenous injection),or followed immediately by KM (500 mg/kg,intramuscular injection).The hearing function was assessed by auditory brainstem response (ABR) measurement in response to click and/or tone bursts at 4,8,12,16,20,24,and 32 kHz.The static microcirculation status in the stria vascularis after a single EA injection was evaluated with eosin staining.The pathological changes in cochlear and vestibular hair cells were also quantified after co-administration of EA and KM.After a single EA injection,blood flow in vessels supplying the stria vascularis rapidly diminished.However,the blood supply to the cochlear lateral wall partially recovered 5 h after EA treatment.Threshold changes in ABR were basically parallel to the microcirculation changes in stria vascularis after single EA treatment.Importantly,disposable co-administration of EA and KM resulted in a permanent hearing loss and severe damage to the cochlear hair cells,but spared the vestibular hair cells.Since the cochlear lateral wall is the important part of the blood-cochlea barrier,EA-induced anoxic damage to the epithelium of stria vascularis may enhance the entry of KM to the cochlea.Thus,experimental animal model of selective cochlear damage with normal vestibular systems can be reliably created through co-administration of EA and KM.