5种胃肠激素样内分泌细胞在斜带石斑鱼稚鱼期消化道中的定位

Location of 5 types of gastrointestinal hormone endocrine cells in digestive tract of juvenile Epinephelus coioides

应用免疫细胞化学SABC方法,用5-羟色胺(5-Hydroxytryptamine,5-HT)、生长抑素(Somatostatin,Som)、P物质(Substance P,SP)、胃泌素(Gastrin,GAS)和神经肽Y(Neuropeptide,NPY)5种特异性哺乳类胃肠激素抗血清对斜带石斑鱼(Epinepheluscoioides)稚鱼期的消化道进行免疫细胞化学定位。结果显示,5-HT-和Som-样免疫活性细胞定位在斜带石斑鱼稚鱼的胃各部,包括胃贲门部、胃体和胃幽门部;SP-、GAS-样免疫活性细胞则在胃和肠均存在,其中SP-样细胞定位在胃体部和胃幽门部以及整个肠道,GAS-样细胞则从胃幽门部至肠道各段均存在;NPY-样免疫活性细胞仅在肠道中被检测到。根据这5种胃肠激素样内分泌细胞的形态、染色强度及其分布,可判断其在稚鱼期已经发育成熟,已像成鱼胃肠激素内分泌细胞一样,调节消化道的运动和消化液的分泌。本研究结果提示,斜带石斑鱼稚鱼死亡的原因可能与其胃肠激素样内分泌细胞的功能没有直接关系。

Five kinds of mammalian antisera—5-hydroxytryptamine（5-HT）,somatostatin（Som）,substance P（SP）, gastrin（GAS）and neuropeptide Y（NPY）—were used to locate the endocrine cells in the digestive tract of juvenile Epinephelus coioides by immunocytochemical SABC method.The results showed that 5-HT immunoreactive（-ir）and Som-ir cells were located in various parts of stomach,including stomachus cardiacus,stomachus fundus and stomachus pyloricus;SP-ir and GAS-ir cells were found in both stomach and gut;SP-ir cells were located in stomachus fundus, stomachus pyloricus and whole intestine;GAS-ir cells could be found from stomachus pyloricus to different parts of gut. NPY-ir cells were only detected from foregut to hindgut.Based on the shape,staining intensity and localization of these 5 kinds of gastrointestinal hormone endocrine cells,it is indicated that these cells in juvenile Epinephelus coioides might have developed and matured and could be involved in regulation of gastrointestinal motor and secretion of digestive juice as those in adult fish.These results suggest for the first time that death of juvenile Epinephelus coioides might have no relationskip with the function of gastrointestinal hormone secreting cells,and thus provided a new clue for tracing the reason of the death in juvenile stage.In addition,the possible physiological functions of these cells were discussed in this paper.