乙酰唑胺对豚鼠内耳超微结构影响的研究

Effects of acetazolamide on inner ear ultrastructure in guinea pigs

目的：探讨乙酰唑胺对血管纹和内淋巴囊上皮细胞超微结构的影响。方法：静脉注射乙酰唑胺后，观察不同时相（０、１５、３０ｍｉｎ、１、２ｈ及７ｄ）血管纹、内淋巴囊超微结构的变化。结果：①血管纹内淋巴腔面游离缘空泡在注射乙酰唑胺后３０ｍｉｎ和１ｈ明显减少，１周后空泡消失，边缘细胞和中间细胞各种细胞器减少，线粒体变性；②内淋巴囊上皮细胞超微结构在注射乙酰唑胺３０ｍｉｎ后出现改变，１ｄ时最为明显，主要表现为暗、亮细胞胞核电子密度下降，胞浆内核糖体、内质网及线粒体减少，顶浆区和底部的胞饮小泡明显减少，细胞间隙变窄，甚至塌陷。２ｈ后血管纹的内淋巴囊的变化基本恢复正常。结论：静脉注射乙酰唑胺可以使血管纹及内淋巴囊超微结构发生一系列病理改变，提示其可能抑制血管纹分泌及内淋巴囊的经上皮重吸收功能，使内淋巴囊分泌的重吸收率下降。

Objective: To explore the effects of acetazolamide on the ultrastructure of stria vascularis and endolymphatic sac. Methods: After the guinea pigs were intravenously injected with acetazolamide, the changes of the ultrastructure of stria vascularis and endolymphatic sac were observed at the different time phases. Results: 1) 30 min and 1 h after the injection, the number of vacuoles and vesicles along the endolymphatic surface of the stria vascularis was markedly decreased and even disappeared 1 week later. The number of all kinds of organelles in the marginal and intermediate cells was reduced. Degeneration of some mitochondria and intracellular and intercellular edema were seen. 2) 30 min after the injection, prominent changes in the endolymphatic sac epithelial cells could be seen. The changes were even more obvious 30 min later. The most conspicuous change was a general reduction in the density of the dark and light cells which was accompanied with a decreased number of cell organelles to give these cells an'empty' appearance. The space between the epithelia were narrow and even totally collapsed. 2 h after the injection, the normal cell structure of stria vascularis and endolymphatic sac were almost reconstructed. Conclusion: The intravenous injection of acetazolamide may cause pathological changes of stria vascularis and endolymphatic sac, which suggests that acetazolamide might inhibit the functions of secretion and reabsorption of the cochlear endolymph.