摘要
应用组织学方法研究三疣梭子蟹胚胎期中枢神经系统的发生和发育,光学显微镜下镜检切片,在第二期卵内无节幼体阶段开始观察到脑;第二期卵内状幼体阶段,前脑由视神经层、侧原脑和中央原脑组成,与位于食道两侧的中脑和后脑形成完整的脑。三疣梭子蟹胚胎期腹神经链由1对大颚、2对小颚和2对颚足所对应的神经节以及腹部神经链组成。光镜下大颚神经节可于第二期卵内无节幼体阶段观察到,2对小颚和2对颚足神经节则在第二期卵内状幼体阶段观察到;腹部神经链则在第三期卵内状幼体阶段观察到。三疣梭子蟹胚胎期中枢神经系统由脑和腹神经链组成,脑由前脑、中脑和后脑组成,脑位于背部,通过2条围食道神经与腹神经链相连。中枢神经系统的不同部分的形成在胚胎发育过程中具有阶段性差异。
Neurogenesis and development of the central nervous system in the embryo stage of swimming crabs, Portunus trituberculatus, were studied by the histological method. The brain appeared at the egg-nauplius stage Ⅱ and was composed of protocerebrum, deutocerebrum and tritocerebrum under microscope. The protocerebrum was composed of lamina ganglionaris, lateral protocerebrum and medial protocerebrum at the egg-zoea stage Ⅱ, and olfactory lobe appeared and arranged beside the esophagus with deutocerebrum and tritocerebrum. The ventral nerve cord of the crab in the embryo included 1 pair mandibular neuromere, 2 pairs neuromeres of maxillae, 2 pairs neuromeres of maxillipede and abdomen nerve cord. Under microscope, the mandibular neuromere appeared at the egg-nauplius stage Ⅱ, the neuromeres of maxillae and neuromeres of maxillipede appeared at the egg-zoea stage Ⅱ, and the abdomen nerve cord formed at the egg-zoea stage Ⅲ. The central nervous system was composed of brain and ventral nerve cord in the embryo stage of the swimming crab. The brain was composed of protocerebrum, deutocerebrum and tritocerebrum. The brain connected to the suboesophageal ganglia with circumoesophageal fibre. The forming time of the part of the central nervous system showed difference in the embryonic development.
基金
国家自然科学基金资助项目(39370089)
浙江省动物学重点扶植学科资助项目(030201)
