中华绒螯蟹神经系统及其胚后发育的组织学观察

为完善中华绒螯蟹神经系统组织学相关资料,文章采用石蜡切片和苏木精—伊红染色技术对中华绒螯蟹神经系统及其胚后发育组织学特点进行了研究。结果表明,中华绒鳌蟹中枢神经系统在Ⅰ期溞状幼虫已见雏形,但前、中、后脑未愈合,前脑较小;Ⅱ期溞状幼虫前脑体积增大;Ⅲ期溞状幼虫中、后脑向上迁移与前脑愈合,到Ⅴ期溞状幼虫,前脑、中脑、后脑完全愈合并迁移到两眼之间;大眼幼虫和稚蟹脑具备了六边形形态。食道下神经节与胸神经节的两条神经索在Ⅰ期溞状幼虫呈分离状态,Ⅱ期溞状幼虫时开始愈合,至Ⅳ期溞状幼虫完全结合。腹神经链在Ⅰ期溞状幼虫发育不完全,Ⅲ期溞状幼虫形成两条神经索,Ⅳ期溞状幼虫两条神经索联系紧密。Ⅴ期溞状幼虫食道下神经节与胸神经节高度愈合,腹神经链发育完全,并在大眼幼虫期开始与胸神经节愈合。胸腹神经团的3个组成部分在稚蟹期达到完全愈合。

Histological Observation of Nervous System and Postembryonic Development of Chinese Mitten Crab Eriocheir sinensis

Histological features of nervous system and postembryonic development were studied in Chinese mitten crab Eriocheir sinensis by paraffin section and HE staining.The results showed that in spite of separation of the forebrain, midbrain and hindbrain, various parts of central nervous system had formed in phase I of the zoea larvae with a smaller forebrain.The brain volume increased in phase Ⅱ of the zoea.The midbrain and hindbrain migrated upward to be combined with forebrain in phase Ⅲ of the zoea.In phase Ⅴ of the zoea larvae, three parts of the brain healed completely and located between the eyes.A hexagon-shaped brain formed in the megalopa larvae and the juvenile crab.Two nerve cords of lower esophageal ganglia and the thoracic ganglia separated in phase I of the zoea, which began to combine in phase Ⅱ of the zoea and fully integrated in phase Ⅲ of the zoea.Ventral nerve chain developed incompletely in phase I of the zoea and formed two nerve cords in phase Ⅲ of the zoea.Two nerve cords contacted closely in phase Ⅳ of the zoea.The lower esophageal ganglia and the thoracic ganglia fully developed in phase Ⅴ of the zoea.In the megalopa larvae, ventral nerve chain began to heal with thoracic ganglia.Three components of abdominal nerve group were fully consolidated in the juvenile crab.