Wiederhold M L, Sheridan C E, Smith N K
Division of Otorhinolaryngology, The University of Texas Health Science Center at San Antonio, USA.
Scan Electron Microsc. 1986(Pt 2):781-92.
The gravity sensors of all molluscs phylogenetically below the cephalopods are spherical organs called statocysts. The wall of the sphere contains mechanosensory cells whose sensory cilia project into the lumen of the cyst. The lumen is filled with fluid and dense "stones", the statoconia or statoliths, which sink under the influence of gravity to load, and stimulate, those receptor cells which are at the bottom. The statoconia of Aplysia californica are shown to be calcified about a lamellar arrangement of membranes. Similar lamellar membrane arrangements are seen within the receptor cells, and their possible role in the formation of the statoconia is discussed. SEM of unfixed statoconia reveals plate-like crystallization on their surface. Elemental analysis shows a relatively high Sr content, which is of interest, since others have recently reported that Sr is required in the culture medium of several laboratory reared molluscs in order for the statoconia to develop.
在系统发育上低于头足类的所有软体动物的重力传感器都是称为平衡囊的球形器官。球体壁包含机械感觉细胞，其感觉纤毛伸入囊腔。囊腔内充满液体和致密的“石头”，即平衡石，它们在重力影响下沉降，从而加载并刺激底部的那些受体细胞。加利福尼亚海兔的平衡石显示为围绕膜的层状排列而钙化。在受体细胞内也观察到类似的层状膜排列，并讨论了它们在平衡石形成中的可能作用。未固定的平衡石的扫描电子显微镜显示其表面有板状结晶。元素分析表明锶含量相对较高，这很有趣，因为最近其他人报告说，为了使平衡石发育，几种实验室饲养的软体动物的培养基中需要锶。
