高浓度钙离子胁迫对褐牙鲆幼鱼鳃黏液细胞数量、超微结构及分泌方式的影响

Effects of High Calcium Concentration Stress on Number,Ultrastructure and Secretion of Mucous Cells in Juvenile Paralichthys olivaceus Gill

利用光学显微镜和透射电子显微镜,研究了高浓度钙离子(37.5±0.1)mmol/L胁迫对褐牙鲆(Paralichthys olivaceus)幼鱼鳃黏液细胞数量、超微结构及分泌方式的影响。结果表明,高浓度钙离子组实验鱼鳃弓黏液细胞的数量与对照组无显著差异(P>0.05);高浓度钙离子组和对照组实验鱼鳃丝黏液细胞的超微结构相同,未成熟黏液细胞呈棒状,具发达的高尔基体和粗面内质网,细胞核近圆形,位于细胞底部,细胞顶膜在鳃上皮组织表面凹陷形成分泌腔,成熟黏液细胞体积较大,呈圆形,黏液颗粒排列紧密,充满整个细胞,基质密度大,细胞器位于细胞底部,细胞核形状不规则;高浓度钙离子组和对照组实验鱼鳃丝黏液细胞的分泌方式相同,均为顶浆分泌,但高浓度钙离子组实验鱼黏液细胞分泌活动旺盛,大量黏液正在向胞外排放,而对照组黏液细胞的黏液分泌量较少。研究认为,褐牙鲆幼鱼对高浓度钙离子胁迫具有较强的耐受能力。

The effects of high calcium concentration stress on number,ultrastructure and secretory process of mucous cells in the gill of juvenile Paralichthys olivaceus were investigated by light microscope and transmission electron microscopy(TEM).The results showed that there was no significant difference in the number of mucous cells in gill arch between high calcium concentration group and control group(P>0.05).No difference in untrastructure of mucous cells in gill filament between the two experimental groups was observerd.Immature mucous cell was club-shaped and contained developed Golgi apparatus and rough endoplasmic reticulum.The nucleus was round and located in the base of the cell and the prominent crypt was curved in the surface of the gill epithelial tissue.Well-developed mucous cell was round and bigger than immature cell.The cell was filled with mucous granules and the whole organelles were compressed in the basal part of the cell.The cytoplasmic regions were electron dense and the nucleus was irregular.The secretory process of mucous cells in gill filament was same between the two experimental groups,belonging to apocrine secretion.However,the secretory activity of mucous cells was vigorous with discharging massive mucus in high calcium concentration group,while it's weak in control group.The results indicated that juvenile P.olivaceus had strong tolerance of high calcium concentration stress.