点带石斑鱼仔稚鱼消化系统黏液细胞的类型与分布

Types and distribution of mucous cells in larval and juvenile digestive tract of Epinephelus malabaricus(Bloch & Schneider)

利用组织学切片及AB-PAS组化染色技术对点带石斑鱼0～28日龄仔稚鱼消化道(口咽腔、食道、胃、肠)不同类型黏液细胞的发生与发育进行了系统的研究。点带石斑鱼黏液细胞分成Ⅰ～Ⅳ共4种着色类型和囊状、梨状、杯状3种形态类型。结果表明,点带石斑鱼黏液细胞最早出现在3日龄仔鱼的口咽腔部位。12日龄之前的黏液细胞数量较少,且主要以Ⅱ型为主,形态上主要为囊状细胞。12～15日龄黏液细胞的数量出现急剧增长,其空间分布模式也随之基本形成。之后日龄的样本中,黏液细胞以Ⅲ、Ⅳ型为主,而I、Ⅱ型黏液细胞所占比例较低。口咽腔、食道的黏液细胞以囊状、梨状为主,胃、肠黏液细胞早期为囊状,随后梨状细胞逐渐增多,最终以杯状细胞为主。食道前段、肠前段的黏液细胞存在显著的差异,但此两段均为黏液细胞的主要分布场所。

Development and distribution of mucous cells in the digestive tracts （oropha- ryngeal cavity, esophagus, stomach, and intestine） of larval and juvenile （0-28 dph） Epi- nephelus malabaricus （Bloch ~ Schneider） were observed and analyzed by the method of histological sections and AB-PAS histochemical staining techniques. Mucous cells of E. malabaricus were classified into I - IV types based on different staining and three morphological shapes （cystic, pear-shaped and cup-shaped）. The result showed that mucous cells first appeared in the oropharyngeal cavity in 3 dph larvae of E. malabaricus. The number of mucous cells before 12dph were few and mainly type II and cystic. The number of mucous cells increased rapidly since 12-15 dph, and the spatial distribution patterns of mucous cells in larval digestive tract were basically formed. There were more type III and type IV mucous cells than type I and type II after this period. In the oropharyngeal cavity and esophagus, mucous cells were mainly cystic and pear-shaped in the early samples. The mucous cells in stomach and intestine were cystic cells, then, pear-shaped cells gradually increased, ultimately, goblet cells were the majority. There are significant morphological differences between anterior esophagus and anterior intesti nal, and they are both the main distribution locations of mucous cells.