Twenty-four guinea pigs with normal Preyer's reflex were exposed to the octave bands of noise centered at 63 Hz and 4 kHz, 110 dB SPL. The duration of exposure was 4 and 8 hours respectively. The permanent shift o...Twenty-four guinea pigs with normal Preyer's reflex were exposed to the octave bands of noise centered at 63 Hz and 4 kHz, 110 dB SPL. The duration of exposure was 4 and 8 hours respectively. The permanent shift of the guinea pigs at the above two frequencies was at 4-8 kHz. As the duration of exposure were 4 hours, the threshold shift at 63 Hz was smaller than that at 4 kHz. But as the duration of exposure was 8 hours, the threshold shift at 63 Hz and 4 kHz was almost the same. No morphological change of the inner ear was observed in the guinea pigs exposed for 4 hours at the octave bands of noise centered at 63 Hz and 4 kHz, but ultrastruetural abnormalities were noted. After the animals were exposed for 8 hours, morphological, nltrastructural changes in the inner ear were observed. The main pathologic changes were seen at the second torn of the cochlea. These changes in hearing physiology and pathology suggest that a high intensive low frequency noise can result in high frequency hearing loss and that the use of A-weighted levels of specific damage risk criteria for noise sources may be inappropriate.展开更多
Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and e...Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models.展开更多
To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with au...To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses （ABR）. The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells （OHCs） loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results： An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa （P〈0.01）. The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%± 5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection （P 〈0.01 ）. All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug （ P 〈 0.01 ）. Conclusions. The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.展开更多
Objective： To describe several approaches of ear surgeries for experimental studies in rats. Methods： Anesthetized rats were prepared for demonstration of various ear surgery approaches designed to optimize experime...Objective： To describe several approaches of ear surgeries for experimental studies in rats. Methods： Anesthetized rats were prepared for demonstration of various ear surgery approaches designed to optimize experimental outcomes in studies with specific goals and exposure requirements. The surgical approaches included the posterior tympanum, superior tympanum, inferior tympanum and occipital approaches. Results： The middle ear cavity and inner ear were successfully exposed from different angles via the mentioned surgical approaches. For example, electrode placement for recording of cochlear bioelectric responses was easily achieved through the posterior tympanum or inferior tympanum approach. Alternatively, drug delivery or gene transfection via round window membrane was most easily accomplished using the posterior tympanum approach. Cochlear perfusion of protective or ototoxic drugs was best performed using the inferior tympanum approach. Ossicular chain interruption to induce a prolonged conductive hearing loss was readily achieved using a superior tympanum approach. Lastly, surgical destruction of the endolymphatic sac to induce experimental endolymphatic hydrops was readily performed via an occipital surgical approach.Conclusion： These standardized surgical approaches can be applied in scientific studies of the ear with different purposes covering electro- physiology, conductive hearing loss, intra-cochlear drug perfusion and experimental studies relevant to Meniere＇s disease.展开更多
目的分析用1000Hz探测音测试不同体积中耳内积液情况下的鼓室导抗,评价用高频探测音进行鼓室导抗检测在鼓室积液诊断中的作用。方法使用GSI33中耳分析仪对实验性中耳积液的白色豚鼠进行226Hz和1000Hz探测音的鼓室导抗测试,并对结果进行...目的分析用1000Hz探测音测试不同体积中耳内积液情况下的鼓室导抗,评价用高频探测音进行鼓室导抗检测在鼓室积液诊断中的作用。方法使用GSI33中耳分析仪对实验性中耳积液的白色豚鼠进行226Hz和1000Hz探测音的鼓室导抗测试,并对结果进行统计学分析。结果使用Graph Pad Prism 4.0统计软件进行统计学分析,结果显示所有实验组的鼓室峰压值均与对照组有显著性差异,且随着中耳积液量增加,鼓室导抗峰压值有降低的趋势。结论1000Hz探测音的声导抗检查可以反映中耳腔内的积液,鼓室导抗图曲线参数因中耳积液量不同而有差异。展开更多
文摘Twenty-four guinea pigs with normal Preyer's reflex were exposed to the octave bands of noise centered at 63 Hz and 4 kHz, 110 dB SPL. The duration of exposure was 4 and 8 hours respectively. The permanent shift of the guinea pigs at the above two frequencies was at 4-8 kHz. As the duration of exposure were 4 hours, the threshold shift at 63 Hz was smaller than that at 4 kHz. But as the duration of exposure was 8 hours, the threshold shift at 63 Hz and 4 kHz was almost the same. No morphological change of the inner ear was observed in the guinea pigs exposed for 4 hours at the octave bands of noise centered at 63 Hz and 4 kHz, but ultrastruetural abnormalities were noted. After the animals were exposed for 8 hours, morphological, nltrastructural changes in the inner ear were observed. The main pathologic changes were seen at the second torn of the cochlea. These changes in hearing physiology and pathology suggest that a high intensive low frequency noise can result in high frequency hearing loss and that the use of A-weighted levels of specific damage risk criteria for noise sources may be inappropriate.
基金supported by the National Key Research and Development Program of China (2021YFA0805902,2022YFF0710703)National Natural Science Foundation of China (32201257)+1 种基金Science and Technology Innovation Project of Xiongan New Area (2022XAGG0121)Young Elite Scientists Sponsorship Program by the China Association for Science and Technology (2019QNRC001)。
文摘Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models.
文摘To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses （ABR）. The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells （OHCs） loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results： An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa （P〈0.01）. The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%± 5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection （P 〈0.01 ）. All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug （ P 〈 0.01 ）. Conclusions. The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.
文摘Objective： To describe several approaches of ear surgeries for experimental studies in rats. Methods： Anesthetized rats were prepared for demonstration of various ear surgery approaches designed to optimize experimental outcomes in studies with specific goals and exposure requirements. The surgical approaches included the posterior tympanum, superior tympanum, inferior tympanum and occipital approaches. Results： The middle ear cavity and inner ear were successfully exposed from different angles via the mentioned surgical approaches. For example, electrode placement for recording of cochlear bioelectric responses was easily achieved through the posterior tympanum or inferior tympanum approach. Alternatively, drug delivery or gene transfection via round window membrane was most easily accomplished using the posterior tympanum approach. Cochlear perfusion of protective or ototoxic drugs was best performed using the inferior tympanum approach. Ossicular chain interruption to induce a prolonged conductive hearing loss was readily achieved using a superior tympanum approach. Lastly, surgical destruction of the endolymphatic sac to induce experimental endolymphatic hydrops was readily performed via an occipital surgical approach.Conclusion： These standardized surgical approaches can be applied in scientific studies of the ear with different purposes covering electro- physiology, conductive hearing loss, intra-cochlear drug perfusion and experimental studies relevant to Meniere＇s disease.
文摘目的分析用1000Hz探测音测试不同体积中耳内积液情况下的鼓室导抗,评价用高频探测音进行鼓室导抗检测在鼓室积液诊断中的作用。方法使用GSI33中耳分析仪对实验性中耳积液的白色豚鼠进行226Hz和1000Hz探测音的鼓室导抗测试,并对结果进行统计学分析。结果使用Graph Pad Prism 4.0统计软件进行统计学分析,结果显示所有实验组的鼓室峰压值均与对照组有显著性差异,且随着中耳积液量增加,鼓室导抗峰压值有降低的趋势。结论1000Hz探测音的声导抗检查可以反映中耳腔内的积液,鼓室导抗图曲线参数因中耳积液量不同而有差异。
