不同pH值对三角帆蚌珍珠质分泌的影响

运用多种组织化学方法和透射电镜技术，研究了５种ｐＨ水环境（ｐＨ５、６、７、８、９）对三角帆砷外套膜珍珠质分泌的影响机制，结果表明，在中性水环境中，贝体能积极地从外界水环境中吸收钙，并能旺盛地合成和分泌贝壳珍珠层及珍珠有机基质前体物质，持续的酸性水环境导致贝体的钙严重丢失，并引起珍珠质分泌细胞对有机基质前体物质的合成和分泌能力减弱，持续的碱性水环境虽能导致贝体对钙的积累，但珍珠质分泌细胞合成和分泌珍

EFFECTS OF pH ON NACRE SECRETION OF FRESHWATER PEARL MUSSEL(HYRIOPSISCUMINGII)

It is the environmental factors inside and outside pearl mussel that determine the secretion of the nacre. In this article, the effect of different water pH (pH 5, 6, 7, 8, 9)on the secretion of nacre of freshwater pearl mussel Hyriopsis cumingii were studied with histochemical methods and transmission electron microscopy. By this study, it was found that the secretion of nacre was hightly related to the water pH, and the water pH indirectly affected the normal secretion of the nacre of the mussel by directly disturbing its calcium ionic regulation and the synthesizing and secreting abilities of its mantle's outer epithelial cells and pearl-sac epithelial cells.In neutral pH (pH7) water, the metabolic activities of the outer epithelial cells of the mantle and the pearl-sac epithelial cells were very active, and they could actively synthesize and secret the components of the organic matrix of shell nacre and pearl (such as protein and neutral polysaccaride etc. ), and supply enough calcium for the nacre formation in Hyriopsis cumingii However, constant acidic water induced the failure of calcium ionic regulation of the mussel which resulted in the calcium loss and calcium shortage for nacre formation, and also decreased the synthesis and secretion of the components of the organic matrix in the nacre-secreting cells, all of which would be disadvantageous to the macre secretion. Constant alkaline water caused the mussel to culminate calcium, and to decrease the supply of the components of the organic matrix,which would also be disabvantageous to nacre secretion. The synthesizing and secreting activities of secretory cells of nacre would be affected more seriously by water pH with increasing acidic or alkaline degree.