采用组织学和电镜技术对曼氏无针乌贼的副缠卵腺及腺体细胞进行了研究。结果表明,副缠卵腺由副缠卵腺壁、腺体小管和结缔组织构成。腺体小管由一层上皮细胞排列围成,各个管道之间通过典型的结缔组织复合体连接在一起;结缔组织复合体由肌肉纤维和血管等构成。小管上皮细胞靠近管腔面着生有微绒毛和纤毛,胞质中有大量的球状小泡分泌物,有的球状小泡被囊泡包裹,通过胞吐作用释放到细胞外,并在纤毛摆动的作用下运送出管道外;腺体管道内存在着大量的共生细菌,呈棒状或者杆状;推测其共生细菌来自于乌贼生活水域的"水平传递"。
Histology and ultrastructure of the accessory nidamental gland (ANG) of Sepiella maindroni were investigated using light and transmission electron microscopy.The ANG was found to consist of an accessory nidamental wall,connective tissue,and many tubules,manifesting certain structural features of a secretory organ that contain many tubules haboring dense populations of coccoidand rod-shaped bacteria.The tubule wall was found to be lined by epithelial cells containing many cytoplasmic vesicles.Based on the ultrastructural observation,we postulated that these vesicles might be secreted through exocytosis.We hold the ANG may play a secretory role in the reproductive cycle and coat the ovulated eggs with a layer of symbiotic bacteria that can ward off egg pathogens;and moreover the symbiotic bacteria may come from environmental seawater rather than from the proceeding S.maindroni through vertical transmission via the egg case sheath.