Objective To discuss the preventive and therapeutical effects of calcium channel blockers in a guinea pig model of Tympanosclerosis. Methods An animal model of Tympanosclerosis was established by placing pathogenic bacteria in both ears of the guinea pigs. Drops of a calcium channel blocker, diltiazem, were added in the left ear to inhibit the secretion and chemotaxis activity of macrophages, thereby inhibiting bone morphogenetic protein-2 (BMP-2) expression and reducing calcium salt deposits, so as to prevent or delay the onset of tympanosclerosis (the experiment ear). Drops of 0.9% NS were placed in the right ear as the control. Observation targets included 1) inflammatory cells, granulation tissue and calcareous de-position in middle ear mucosa under an optical microscope;2) types of cells infiltrating the middle ear tissue and BMP-2 ex-pression demonstrated by CD68 and BMP-2 antibody;and 3) fibrocyte morphology changes, macrophage chemotaxis, fibrous hyperplasia and calcium salt deposits within the middle ear tissue near the tympanic membrane under a transmission electron microscope. Results Optical microscopy showed increased inflammation in experiment ears compared to the control. The muco-sae inside the bulla in both experiment and control ears showed high CD68 expression which was proportional with the severity of infection. BMP-2 staining in the mucosae of the control ear was significantly higher than that of the experiment ear, even when they showed similar levels of infection, clustering especially in the submucosa, possibly from macrophage agglomeration with increased secretion of BMP-2. Electron microscopy (TEM) in the experiment ear showed some columnar epithelial cells and only low grade fibrous hyperplasia, with infiltration of inflammatory cells, lymphocytes and a few macrophages but no calci-um salt deposits. In contrast, TEM in the control ear showed severe tissue damage, with hardly any recognizable normal tissue cells or structures and piles of macrophages filled with phagosomes in some areas, as well as significant fibrous hyperplasia and calcium salt deposits. Conclusion The study indicates that application of calcium antagonists in the middle ear can inhibit secretion and chemotaxic activities of the macrophage, reduce local inflammatory damage and thereby inhibit bone morphoge-netic protein-2 expression and calcium salt deposits, so as to prevent or delay the onset of tympanosclerosis.%目的：通过豚鼠中耳炎模型探讨局部应用钙离子拮抗剂抑制鼓室硬化的可能机制。方法通过对豚鼠人工创伤双中耳种植病原菌的方式建立慢性中耳炎的模型，并对左耳每日滴用钙离子拮抗剂地尔硫卓（CBBS）液灌注治疗，右耳为对照耳，滴生理盐水的方法，来研究中耳局部使用钙离子拮抗剂是否能通过抑制巨噬细胞的趋化分泌活动，进而抑制骨形成蛋白-2表达，较少钙盐沉积，从而阻止或延缓MS、TS发生。观察数据1）光学显微镜下观察鼓室粘膜炎性细胞、肉芽组织及硬化灶病理学改变；2）分别使用CD68及BMP-2抗体进行标记，确定中耳组织内侵入的细胞类型和BMP-2表达情况。3）取中耳近鼓膜处标本送投射电镜观察粘膜组织纤维细胞内形态改变、巨嗜细胞趋化情况及组织内纤维增生和钙离子沉着情况。结果光学显微镜下对照耳听泡内炎症较实验耳严重；CD68及BMP-2染色情况：实验耳及对照耳粘膜及听泡内均有较高CD46的表达并和感染的严重度呈正比，对照耳稍多；对照耳粘膜BMP-2染色明显高于实验耳，即使感染程度接近仍有明显差异，并且在粘膜下层会出现较密集的群聚现象，考虑为大量的巨嗜细胞集聚并有较高的BMP-2分泌。电镜改变：实验耳标本内尚可见部分柱状上皮细胞，仅有少量胶原纤维增生，炎症细胞淋巴细胞为主，很少见到巨嗜细胞，基本看不到钙盐沉积。对照耳标本组织破坏严重，部分区域几乎看不到多少正常组织细胞，已无法辨认出柱状上皮细胞，可见成堆的充满吞噬泡的巨嗜细胞，胶原纤维增生明显，并伴有成堆的钙盐沉积。结论动物模型实验提示中耳局部使用钙离子拮抗剂能通过抑制巨噬细胞的趋化分泌活动，减轻局部炎症破坏，进而抑制骨形成蛋白-2表达，较少钙盐沉积，从而阻止或延缓鼓室硬化的发生。
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