Lippe W R, Westbrook E W, Ryals B M
Department of Otolaryngology, University of Washington School of Medicine, Seattle 98195.
Hear Res. 1991 Nov;56(1-2):203-10. doi: 10.1016/0378-5955(91)90171-5.
Hair cell loss in the avian cochlea partially recovers following both acoustic trauma and aminoglycoside intoxication. DNA labeling with tritiated thymidine has shown that the restoration of cell number following acoustic trauma results from the production of new hair cells by mitotic division. The purpose of the present study was to determine if mitosis also contributes to the recovery of hair cell number which occurs following aminoglycoside intoxication. Chickens received daily injections of either gentamicin sulfate or distilled water for 10 consecutive days. During the latter 7 days of this period, all birds were also injected with [3H]thymidine. Following postinjection survival periods of 3 or 6 days, one papilla from each bird was processed for autoradiography and the other for scanning electron microscopy (SEM). Incorporation of [3H]thymidine was seen over hair cells and support cells in experimental papillae in regions of hair cell loss. No labeling was seen outside of damaged regions or in the papillae of control birds. SEM showed that damaged regions in experimental birds contained cells similar in appearance to developing auditory hair cells in avian embryos. These results show that the restoration of hair cell number following aminoglycoside toxicity results from the production of new cells by mitosis.
鸟类耳蜗中的毛细胞损失在遭受声学创伤和氨基糖苷类中毒后会部分恢复。用氚标记胸腺嘧啶核苷进行DNA标记表明，声学创伤后细胞数量的恢复是由有丝分裂产生新的毛细胞所致。本研究的目的是确定有丝分裂是否也有助于氨基糖苷类中毒后毛细胞数量的恢复。给鸡连续10天每日注射硫酸庆大霉素或蒸馏水。在此期间的后7天，所有鸡还注射了[3H]胸腺嘧啶核苷。在注射后3天或6天的存活期后，每只鸡的一个乳头用于放射自显影，另一个用于扫描电子显微镜（SEM）检查。在实验乳头中毛细胞损失区域的毛细胞和支持细胞上可见[3H]胸腺嘧啶核苷的掺入。在受损区域之外或对照鸡的乳头中未见标记。扫描电子显微镜显示，实验鸡的受损区域含有外观与鸟类胚胎中发育的听觉毛细胞相似的细胞。这些结果表明，氨基糖苷类毒性后毛细胞数量的恢复是由有丝分裂产生新细胞所致。
