摘要
目的 探讨Ca2 +泵间接激活剂佛波酯 (phorbol 12 myristate 13 acetate ,PMA)对噪声性聋的保护作用。方法 杂色豚鼠随机分为 2组 :PMA组和人工外淋巴液组 (对照组 ) ,分别全耳蜗灌流 3μmol/LPMA和人工外淋巴液并暴露于 10 0dBSPL的白噪声持续 12 0min。于噪声暴露前和噪声暴露后 12 0min圆窗记录耳蜗微音电位 (cochlearmicrophonics ,CM)和耳蜗听神经复合动作电位 (compoundactionpotential,CAP)。比较两组相同时间点的CM幅度和CAP阈值。结果 噪声暴露前两组CM幅度和CAP阈值差异无显著性 (P >0 0 5 )。噪声暴露后两组CM幅度下降和CAP阈值升高 ,但PMA组CM幅度高于对照组 ,CAP阈值低于对照组 (P <0 0 5 )。结论 Ca2 +泵间接激活剂PMA对噪声性聋有部分保护作用。
Objective To investigate the possible protective effect of phorbol-12-myristate-13-acetate (PMA), an activator of protein kinase C (PKC) and indirect activator of Ca 2+ pump, on noise-induced hearing loss (NIHL). Methods Twenty guinea pigs were divided randomly into two groups, and then perfused with artificial perilymph solutions in one group and with artificial perilymph solutions containing 3μmol/L PMA in the other one, respectively. All animals were exposed with 100dB SPL white noise for 2 hours. Cochlear microphonics (CM) and compound action potential (CAP) were recorded from the round window (RW) before noise exposure and 2 hours after noise exposure. Results There was no significant difference in CAP threshold and CM amplitude between two groups before noise exposure. A significant difference was observed in CAP threshold and CM amplitude between two groups after noise exposure. The amplitude of CM decreased and the threshold of CAP increased in both group after noise exposure, but in the PMA group the decrease of the amplitude of CM was higher while the increase of threshold of CAP lower than that in control (P<0.05). Conclusion PMA might have partly protective effect on NIHL. These findings indirectly proved that intracellular Ca 2+ overload might involve in the mechanism of NIHL.
出处
《中华耳鼻咽喉科杂志》
CSCD
北大核心
2002年第6期425-427,共3页
Chinese Journal of Otorhinolaryngology
基金
国家自然科学基金资助项目 ( 39870 797)
关键词
钙泵间接激活剂
噪声性聋
保护作用
Hearing loss,noise-induced
Phorbol esters
Calcium channel agonists
Cochlear microphonic potentials
Action potentials
