Tandler B, Toyoshima K, Phillips C J
Department of Oral Biology, School of Dentistry, Case Western Reserve University, Cleveland, Ohio 44106.
Am J Anat. 1990 Dec;189(4):303-15. doi: 10.1002/aja.1001890403.
The principal and accessory submandibular glands of the common vampire bat, Desmodus rotundus, were examined by electron microscopy. The secretory endpieces of the principal gland consist of serous tubules capped at their blind ends by mucous acini. The substructure of the mucous droplets and of the serous granules varies according to the mode of specimen preparation. With ferrocyanide-reduced osmium postfixation, the mucous droplets are moderately dense and homogeneous; the serous granules often have a polygonal outline and their matrix shows clefts in which bundles of wavy filaments may be present. With conventional osmium postfixation, the mucous droplets have a finely fibrillogranular matrix; the serous granules are homogeneously dense. Mucous cells additionally contain many small, dense granules that may be small peroxisomes, as well as aggregates of 10-nm cytofilaments. Intercalated duct cells are relatively unspecialized. Striated ducts are characterized by highly folded basal membranes and vertically oriented mitochondria. Luminal surfaces of all of the secretory and duct cells have numerous microvilli, culminating in a brush borderlike affair in the striated ducts. The accessory gland has secretory endpieces consisting of mucous acini with small mucous demilunes. The acinar mucous droplets contain a large dense region; the lucent portion has punctate densities. Demilune mucous droplets lack a dense region and consist of a light matrix in which fine fibrillogranular material is suspended. A ring of junctional cells, identifiable by their complex secretory granules, separates the mucous acini from the intercalated ducts. The intercalated ducts lack specialized structure. Striated ducts resemble their counterparts in the principal gland. As in the principal gland, all luminal surfaces are covered by an array of microvilli. At least some of the features of the principal and accessory submandibular glands of the vampire bat may be structural adaptations to the exigencies posed by the exclusively sanguivorous diet of these animals and its attendant extremely high intake of sodium chloride.
利用电子显微镜对普通吸血蝙蝠（Desmodus rotundus）的主要和附属颌下腺进行了检查。主要腺体的分泌终末部分由浆液性腺管组成，其盲端由黏液性腺泡覆盖。黏液小滴和浆液性颗粒的亚结构根据标本制备方式的不同而有所变化。采用亚铁氰化物还原锇后固定法时，黏液小滴密度适中且均匀；浆液性颗粒通常呈多边形轮廓，其基质显示出裂隙，其中可能存在成束的波浪状细丝。采用常规锇后固定法时，黏液小滴具有精细的纤维颗粒状基质；浆液性颗粒密度均匀。黏液细胞还含有许多小的致密颗粒，可能是小过氧化物酶体，以及10纳米细胞丝的聚集体。闰管细胞相对未特化。纹状管的特征是基底膜高度折叠且线粒体垂直排列。所有分泌细胞和导管细胞的腔面都有许多微绒毛，在纹状管中形成类似刷状缘的结构。附属腺体的分泌终末部分由带有小黏液半月的黏液性腺泡组成。腺泡黏液小滴含有一个大的致密区域；透明部分有点状密度。半月黏液小滴没有致密区域，由一个轻基质组成，其中悬浮着精细的纤维颗粒状物质。一圈由其复杂分泌颗粒可识别的连接细胞将黏液性腺泡与闰管分隔开。闰管缺乏特殊结构。纹状管与主要腺体中的对应结构相似。与主要腺体一样，所有腔面都覆盖着一排微绒毛。吸血蝙蝠主要和附属颌下腺的至少一些特征可能是对这些动物完全以血为食及其随之而来的极高氯化钠摄入量所带来的紧急情况的结构适应。
