摘要
目的:观察气体冲击致豚鼠耳蜗损伤后天冬氨酸特异性半胱氨酸蛋白酶3的表达。方法:实验于2005-01/06在解放军第三军医大学大坪医院野战外科研究所完成。选择健康白色红目豚鼠20只,随机分为正常对照组和气体冲击致伤组,各10只。实验组用30kPa压力气体冲击致伤豚鼠耳蜗,冲击20次,间隔20s/次;正常对照组不进行气体冲击致伤。实验前后测试听性脑干反应阈值,冲击波暴露后12h处死动物制作耳蜗标本。免疫组化法测定天冬氨酸特异性半胱氨酸蛋白酶3的表达。结果:纳入豚鼠20只,均进入结果分析。①实验组听性脑干反应阈值较正常对照组明显上升[(50.94±5.98),(5.60±1.78)dBnHL,t=22.98,P<0.01],听力下降明显。②免疫组织化学染色结果显示实验组豚鼠耳蜗天冬氨酸特异性半胱氨酸蛋白酶3反应阳性,柯蒂氏器及血管纹、螺旋神经节细胞的细胞质内有染色程度不同的棕黄色颗粒分布,染色阳性细胞数以血管纹、螺旋神经节细胞较多,愈近底回愈多,愈近顶回则愈少。对照组无阳性表达。结论:天冬氨酸特异性半胱氨酸蛋白酶3在气体冲击致豚鼠耳蜗损伤后呈阳性表达,提示耳蜗细胞凋亡在冲击波致聋的发病机制中起重要作用。
AIM： To observe the expression of caspase-3 in guinea pigs with cochlear injury induced by air blast.
METHODS： The experiment was performed in the Institute of Battle Surgery, Daping Hospital of Third Military Medical University from January to June 2005. Twenty healthy white guinea pigs with red eyes were randomly divided into normal control group and air-blast injury group with 10 ones in each group. Cochleas of guinea pigs in the experimental group were injured by air blast device for 20 times with an interval of 20 seconds and pressure of 30 kPa; Guinea pigs in the normal control group received no air blast. Auditory threshold value of auditory brainstem response （ABR） was tested before and after experiment, and animals were sacrificed and made into cochlear samples by exposing into shock wave for 12 hours. Expression of caspase-3 was tested with immunohistochemical method.
RESULTS： Twenty included guinea pigs were involved in the analysis of results. ① Compared with the auditory threshold value of ABR in the normal control group [（50.94±5.98）, （5.60±1.78）d BnHL, t=22.98, P 〈 0.01], it was injured obviously in the experimental group. ② lmmunohistochemieal staining study showed that caspase-3 positive reaction appeared in the experimental group. There were staining particles of different degree distributed in intracytoplasms of Corti＇s organ cells, stria vaseularis cells and spiral ganglion cells. Number of staining positive cells, stria baseularis cells and ganglion cells increased, caspase-3 positive reaction staining cochlear cells in basal turn are more than those in apical turn. There was no positive expression in the control group.
CONCLUSION： The expression of caspase-3 is positive in guinea pigs with cochlear injury caused by air blast, which indicates that cochlear cell apoptosis plays an important role in cochlear injury caused by air blast.
出处
《中国临床康复》
CSCD
北大核心
2006年第8期101-103,共3页
Chinese Journal of Clinical Rehabilitation
