扬子鳄消化系统发育的形态学研究  

MORPHOLOGICAL AND DEVELOPMENTAL RESEARCH ON THE DIGESTIVE SYSTEM OF ALLIGATOR SINENSIS

作　　者：李堃[1] 华田苗[1] 陈壁辉[1] 

机构地区：[1]安徽师范大学生命科学学院,安徽芜湖241000

出　　处：《安徽师范大学学报（自然科学版）》2002年第3期266-269,共4页Journal of Anhui Normal University(Natural Science)

基　　金：国家自然科学基金 (3 9470 0 92 );安徽省自然科学基金资助课题 (982 41716)

摘　　要：对近年来扬子鳄消化道和消化腺的胚胎发育、形态结构及有关功能的研究进行了综述 ,获得如下一些结论 :(1)在胚前发育中 ,消化道壁的分层具特定的时空顺序 ,即按照粘膜上皮和固有膜、粘膜下层和环肌层、斜肌或 (和 )纵肌层的先后次序出现 .消化道上皮细胞的特征及其在个体发育中复杂的演变过程可能与其进化历程、消化道的伸长和胚后期食性有关 .(2 )扬子鳄消化道接受植物性神经———胆碱能纤维的支配 ,同时本身具有多种内分泌细胞 ,参与消化活动的调节 .(3)扬子鳄舌腺被认为具有泌盐和分泌粘液两种作用 ,在胚前和胚后期均发现有大型和小型两种舌腺的存在 .(4)扬子鳄肝脏由早期胚胎前肠门边缘内陷的内胚层上皮和脏壁中胚层组织共同发育形成 .发现胚胎期肝细胞在孵育第 30天 (约 2 9℃孵育温度 )已具备糖类和脂类等物质代谢机能 .胚后期肝细胞中脂滴数量比胚前期显著减少 .(5 )扬子鳄胰腺属于由低等向高等进化的原始类型 .在胚前和胚后期 ,胰腺内分泌细胞大多数分散分布 ,少数成群分布 ,未能检测出胰岛素分泌阳性细胞 (B细胞 ) 。Recent research on embryonic development, morphological structure and function of the digestive tract and glands in Alligator sinensis were described and summarized. Some conclusions were drawn as follows: 1) During the pre-natal development, layers in the wall of digestive tract appeared at a certain sequence of time and space, that is from epithelia and lamina propria to submucosa and circular muscle layer, and then to oblique and (or) longitudinal muscle layer. Epithelial cells in the digestive tract showed some features and were found to go through a sophisticated changes during development, which might be related to its evolutionary stages, the growth of length of digestive tract and the food type of Alligator sinensis during post-natal stages. 2) The digestive tract received the control of vegetative nerve-Cholinergic fibers, and at the same time contained many types of endocrine cells, which joined in the regulation of digestive activity. 3) The lingual gland of Alligator sinensis was reported to have two kinds of functions, that is to secrete sodium chloride and mucus. Two types of lingual glands, big and small, were found at both pre-natal and post-natal stages. 4) The liver of Alligator sinensis was formed by the endodermal epithelia invigilated from the edge of foregut door and by surrounding mesoderm during early stages of pre-natal development. It was noted that liver cells had established metabolic mechanism for such substance as carbohydrate and lipid at 30th day of incubation (at about 29℃ incubation temperature). Liver cells at pre-natal stages contained far more Lipid droplets than at post-natal stages. 5) The pancreas of Alligator sinensis is an original type in the evolution of vertebrates. Whether at Pre-natal or post-natal stages, most endocrine cells in pancreas distributed separately and only a few gathered together. It is worthy of further investigation that no positive insulin-secretion cell was detected.

关 键 词：系统发育 扬子鳄 消化系统 形态学 消化道 消化腺 形态结构 

分 类 号：Q959.64[生物学—动物学] Q954