摘要
目的比较抗氧化剂硫辛酸(lipoic acid,LA)经静脉与鼓室两种不同给药途径对急性声损伤后动物耳蜗内细胞凋亡过程的影响。方法48只豚鼠随机分为4组。A:鼓室注射硫辛酸组,不给于噪声暴露;B:单纯噪声暴露组(110dBSPL稳态噪声暴露5h);C:噪声暴露+静脉注射硫辛酸组;D:噪声暴露+鼓室注射硫辛酸组。各组动物于处理前和处理后1、3、5、7d取出豚鼠耳蜗,石蜡包埋、切片。应用原位末端标记技术(TUNEL)标记凋亡细胞,观察耳蜗Corti器、血管纹、螺旋神经节等部位细胞的凋亡特点。结果光镜下Corti器、血管纹、螺旋神经节TUNEL阳性反应细胞表现为细胞核染成棕黄色或棕褐色。硫辛酸经鼓室注射组(A组)未见明显凋亡细胞。噪声暴露后经鼓室注射硫辛酸组(D组)与经静脉注射组(C组)同单纯暴露组(B组)相比,差异有统计学意义(P<0.05)。但C、D两种方式抑制凋亡无明显的差异(P>0.05)。结论110dBSPL噪声暴露5h可导致急性声损伤,引起豚鼠耳蜗组织内细胞的凋亡。抗氧化剂硫辛酸经鼓室与静脉注射对噪声暴露后细胞的凋亡皆有明显的抑制效应,但鼓室注射较静脉注射无明显的优势。
Objective To compare impacts on apoptosis process in cochlear cells by lipoic acid administered either intravenously or intratympanically after acute acoustic trauma.Methods Forty eight guinea pigs were randomly divided into 4 groups.Group A received intratympanic injection of lipoic acid and no noise exposure.Group B was subjected to noise exposure （110 dB SPL,5 h） and no treatment.Group C was exposed to noise and treated with intravenous injection of lipoic acid.Group D was treated with intratympanic injection of lipoic acid after noise exposure.Apoptosis of cells in the organ of Corti,stria vascularis,spiral ganglion and other parts of the cochlea was examined before and immediately after experiment and on Days 1,3,5 and 7.Results TUNEL-positive cells in the organ of Corti,stria vascularis and spiral ganglion were found to have nuclei stained brown or tan under a light microscope.No obvious apoptotic cells were seen in Group A）.After noise exposure,different levels of apoptosis inhibition were noticed among Groups B and C,D （P 0.05）,although the difference was not statistically significant between the two administration routes （P 0.05）.Conclusion Noise exposure at 110 dB SPL 5 h can lead to acute acoustic trauma and induce a variety apoptotic changes in guinea pig cochlear cells.Lipoic acid shows protective effect on apoptosis after noise exposure regardless of administration routes.There is no obvious advantage in employing the intratympanic route.
出处
《中华耳科学杂志》
CSCD
2010年第1期100-104,共5页
Chinese Journal of Otology
基金
首都医学发展基金(编号:2005-2037)
