Caspase-3在白色和杂色豚鼠脉冲噪声损伤耳蜗中的表达

Expression of Caspase-3 in Cochlea of White and Pigmented Guinea Pigs Exposed to Impulsive Noise

【目的】观察Caspase-3在暴露于脉冲噪声中的白色和杂色豚鼠耳蜗中的表达,以探讨黑色素对耳蜗损伤的保护作用机制。【方法】选用白色和杂色豚鼠各8只,暴露于脉冲噪声中复制耳蜗损伤模型。取耳蜗用石蜡包埋、切片,采用免疫组织化学法观察Caspase-3在两组豚鼠耳蜗的表达。【结果】Caspase-3在两组脉冲噪声暴露豚鼠耳蜗中均呈阳性表达,以血管纹和螺旋神经节的表达较强,而且Caspase-3在白色豚鼠耳蜗的表达显著强于杂色豚鼠。【结论】耳蜗黑色素拮抗耳蜗损伤的作用是通过抑制耳蜗Capase-3活性,从而抑制耳蜗细胞的凋亡来实现的。

Objective To observe the expression of Caspase-3 in the cochlea of white and pigmented guinea pigs exposed to impulsive noise, and to explore the protective mechanism of melanin on cochlea damage. Methods Eight white guinea pigs and eight pigmented guinea pigs were exposed to impulsive noise to induce cochlea damage. Then the injured cochlea from the guinea pigs were embedded with paraffin, and cut into slides. The expression of Caspase-3 in the cochlea was examined by the method of immunohistochemistry. Results The expression of Caspase-3 in the cochlea of two kinds of guinea pigs was positive. Caspase-3 expression was much stronger in the area of stria vascularis and spiral ganglion cell, and was much stronger in the white guinea pigs than that in the pigmented guinea pigs. Conclusion The therapeutic mechanism of melanin in counteracting the cochlea damage may be related with the inhibition of cochlea cell apoptosis through inhibiting Caspsae-3 activity in the cochlea.