Fishelson L, Baranes A
Department of Zoology, Tel-Aviv University, Ramat Aviv, Israel.
Anat Rec. 1998 Aug;251(4):417-30. doi: 10.1002/(SICI)1097-0185(199808)251:4<417::AID-AR1>3.0.CO;2-P.
Ampullae of Lorenzini are electrosensitive organs that, together with the olfactory organs, form the main sensory systems for foraging and navigation in skates, rays, and sharks. In sharks, these organs are mainly found on the rostral part of the head. This study describes the morphology and cytology of the ampullar system in the Oman shark, Iago omanensis, which is common in the Red Sea. The sharks were collected in the Gulf of Aqaba, Red Sea, at depths of 300-750 m, by a specially designed net. They were brought to the surface and sacrificed by an overdose of MS222, and their heads were fixed and prepared for LM, TEM, and SEM studies. The ampullae are of the polyvesicular type, and their sensory alveoli are situated on the head only and form groups enclosed in capsules of collagenous connective tissue. The dorsal side of the head features pairs of mediorostral (MRC), laterorostral (LRC), and preorbital (POC) capsules and one frontal capsule (FC), situated at the base of the rostrum in front of the eyes. The ventral side possesses only two, small mandibular (MC) capsules. The number of sensory alveoli differs in each of the capsules, and the largest group of 500 is found in the two mediorostral capsules. Each alveolus is formed by seven to nine sensory vesicles, from which a common tubule, piercing the capsule envelope, extends to a cutaneous pore. Groups of such pores form a pattern typical for Iago. A detailed description is given of the sensory epithelium, kinociliar, and microvillar cells as well as of the supporting cytological elements. The ampullae of Lorenzini in adult I. omanensis are generally similar to those of a number of other studied sharks. However, as the study shows, their number and configuration differ and form a morphological and topographic pattern typical for this species.
罗伦氏壶腹是一种电感应器官，它与嗅觉器官一起，构成了鳐鱼、魟鱼和鲨鱼觅食与导航的主要感觉系统。在鲨鱼中，这些器官主要分布在头部的吻部。本研究描述了阿曼鲨（Iago omanensis）壶腹系统的形态学和细胞学特征，这种鲨鱼在红海较为常见。鲨鱼是在红海亚喀巴湾300 - 750米深处，用专门设计的网捕捞的。它们被带到水面，通过过量注射MS222处死，然后将其头部固定，准备用于光镜、透射电镜和扫描电镜研究。罗伦氏壶腹属于多囊泡型，其感觉小泡仅位于头部，形成被胶原结缔组织囊包裹的群体。头部背侧有一对中吻（MRC）、侧吻（LRC）和眶前（POC）囊，以及一个位于眼睛前方吻部基部的额囊（FC）。腹侧只有两个小的下颌（MC）囊。每个囊中感觉小泡的数量不同，两个中吻囊中发现最大的一组，有500个。每个小泡由七到九个感觉小囊泡形成，从中伸出一个穿透囊包膜的共同小管，延伸到皮肤小孔。这样的小孔群形成了阿曼鲨特有的模式。文中详细描述了感觉上皮、动纤毛细胞和微绒毛细胞以及支持性细胞学成分。成年阿曼鲨的罗伦氏壶腹总体上与其他一些已研究的鲨鱼相似。然而，正如研究所示，它们的数量和形态不同，形成了该物种特有的形态学和拓扑学模式。
