神经营养因子修复神经组织机制的研究:脑细胞生长肽对豚鼠耳蜗毛细胞内酸性磷酸酶的影响(英文)

A study on the mechanism of neurotrophic factors for repair of nerve tissue:effects of cerebrocellular growth peptide on acid phosphatase of hair cells in cochlea of gentamicin induced ototoxic guinea pigs

背景:脑细胞生长肽(cerebrocellulargrowthpeptide,CCGP)对庆大霉素引起的耳蜗毛细胞内酸性磷酸酶(acidphosphatase,ACP)的变化是否有影响?对受损耳蜗组织是否有促进修复的作用?目的:观察CCGP对庆大霉素引起的耳中毒豚鼠ACP的影响。设计:随机对照研究。地点和材料:实验地点:泰山医学院听觉研究室。选用健康杂色豚鼠40只,对照组10只,肌肉注射生理盐水1mL/(kg·d);庆大霉素组15只,肌肉注射硫酸庆大霉素80mg/(kg·d);CCGP组15只,肌肉注射硫酸庆大霉素同庆大霉素组,并肌肉注射CCGP1mg/(kg·d)。各组用药25d。方法:用脑干听觉诱发电位(brainstemauditoryevokedpotential,BAEP)和组织化学方法检测动物听阈的变化和耳蜗毛细胞ACP显色变化。主要观察指标:各组动物BAEP反应阈值和ACP显色变化。结果:用药前BAEP反应阈值犤dB(peSLP)犦:生理盐水组32.62±2.33,庆大霉素组31.87±2.63,CCGP组32.56±2.39。用药后BAEP反应阈值均有不同程度的升高,用药后25dBAEP反应阈值:生理盐水组32.81±2.48,庆大霉素组56.73±17.21,CCGP组42.87±9.95,庆大霉素组、CCGP组与生理盐水组比较,差异均有显著性意义(t=3.113,4.335,P均<0.01),CCGP组与庆大霉素组比较,差异有显著性意义(t=2.700,P<0.05)。

BACKGROUND:Cerebrocellular growth peptides(CCGP) can affect the change of acid phosphatase(ACP) in cochlea induced by gentamicin and accelerate the repair of injured cochlear tissue is unknown.And whether inter neurotrophins have a coordinated effect is also unclear. OBJECTIVE:To investigate the effects of CCGP on ACP in cochlear hair cells of GM induced ototoxic guinea pigs. DESIGN:A randomized controlled trial. SETTING and MATERIALS:The experiment was completed in the Department of Audition, Taishan Medical College.Forty healthy parti colored guinea pigs were selected and randomized into control group of 10 guinea pigs through intramuscular injection of 1 mL/(kg·d) saline,gentamicin group of 15 guinea pigs intramuscularly injected with 80 mg/(kg·d) gentamicin,and CCGP group intramuscularly injected with 1 mL/(kg·d) CCGP.The duration of administration was 25 days. METHODS:The hypoacusis severity and enzymatic activity in the cochlear hair cells were examined by brainstem auditory evoked potential(BAEP) and histochemistry,respectively. MAIN OUTCOME MEASURES:BAEP reaction thresholds and changes of ACP in the cochlear hair cells. RESULTS:Before treatment the BAEP reaction thresholds were (32.62±2.33)dBpeSLP for the saline group,(31.87±2.63) dBpeSLP for the gentamicin group and(32.56±2.39) dBpeSLP for the CCGP group.BAEP reaction thresholds were elevated at different levels after treament.Twenty five days after treatment,the BAEP reaction thresholds were(32.81±2.48),(56.73±17.21) and(42.87±9.95) dBpeSLP for the three groups respectively.There were significant differences between the control group and gentamicin and CCGP groups(t=3.113,4.335,P< 0.01),and between the gentamicin group and CCGP group(t=2.700,P< 0.05).In the control group,the hair cells presented dark brown stained by ACP histochemical staining and arranged in order.ACP histochemical reaction showed that the color disappeared in the hair cells of the gentamicin group. In the CCGP group,no obvious change was found in ACP level, and there was a significant difference between the gentamicin and CCGP groups. CONCLUSION:CCGP can reduce gentamicin induced ototoxicity and autolytic lesion of hair cells induced by destroyed lysosome.