中华绒螯蟹蜕皮过程中体壁结构和主要成分的变化

采用组织化学和原子吸收分析等方法, 研究了中华绒螯蟹蜕皮过程中体壁结构和主要成分的变化。结果显示: 中华绒螯蟹体壁分为上表皮、外表皮、内表皮和膜层, 糖类物质各层均有分布, 胶原纤维分布在除上表皮外的其他各层。在蜕皮前, 糖类、胶原纤维都被重吸收, 体壁上表皮和外表皮在蜕皮前形成, 内表皮和膜层在蜕皮后形成。体壁粗蛋白含量在蜕皮前期(D1-D3-4期)降低(P0.05), 蜕皮后A-B期含量极高(P0.05)。几丁质含量在蜕皮过程中变化不显著(P0.05), 只是在蜕皮前稍有上升。Ca2+和Mg2+含量在蜕皮前D1期显著低于蜕皮间期和蜕皮前其他时期(P0.05), 而蜕皮后A-B期降到最低(P0.05), 蜕下的甲壳中则含有较多的Ca2+和Mg2+ (P0.05)。Cu2+和Zn2+含量除蜕皮后A-B期升高外(P0.05), 其余时期变化不明显(P0.05)。这些研究结果表明, 中华绒螯蟹体壁结构和成分变化与蜕皮周期密切相关。  

STRUCTURAL AND CONSTITUENT CHANGES IN INTEGUMENT DURING THE MOLT CYCLE OF CHINESE MITTEN CRAB ERIOCHEIR SINENSIS

The construction and main constituent of the integument of Eriocheir sinensis were studied by the methods of histochemistry and atomic absorption methods. The results showed that the integument of E. sinensis was composed of four sub-layers from the exterior to the interior: an epicuticle, an exocuticle, an endocuticle, and a membranous layer. The carbohydrates were deposited in all sub-layers and the collagen fibers were deposited in all sub-layers except the epicuticle. Both carbohydrates and collagen fibers were reabsorbed in premolt stages. The epicuticle and exocuticle were synthesized before molt and the endocuticle and membranous layer were synthesized after molt. The contents of integumental crude protein decreased before molt (D1-D3-4) (P0.05) and were extremely high in postmolt A-B stage (P0.05). The integumental chitinous content showed no obvious variation during the molt cycle (P0.05) except a little increase before molt. The contents of Ca2+and Mg2+ in premolt D1 stage were significantly lower compared with the intermolt stage and other stages in premolt (P0.05) and were the lowest in the postmolt A-B stage (P0.05). There were much Ca2+and Mg2+ in the exoskeleton that the animal moulted. The content of Cu2+ and Zn2+ showed no obvious variation except increased in postmolt A-B stage (P0.05). These results indicated that the structural and constituent changes in integument of E. sinensis are coincident with its molt stages.