摘要
本实验取杜长哈杂交母猪和东北民猪各1头,于妊娠第10天取子宫,冲出胚胎,在扫描电镜下观察直径3和9mm 胚泡的内外表面结构。将胚泡分成胚盘区、动物极、侧壁和植物极等4个区进行观察。结果表明,3mm 胚泡的胚盘区外表面仍为滋养层细胞。细胞有3种类型;一种表面有许多圆球形突起和细长突起;另一种是表面有许多细长微绒毛的细胞;还有一种是表面光滑无微绒毛的细胞。胚泡其他区域的外表面滋养层细胞表面结构相同,只是略平坦而已。胚泡壁内面是内胚层细胞,4个区域的细胞结构不同。胚盘区细胞表面有许多密集的微绒毛。从胚盘区经动物极、侧壁到植物极。细胞形态呈规律变化,即细胞由小变大,形态逐渐变扁,表面的微绒毛逐渐减少,细胞周边区域扁平,其上有许多不规则的孔。在植物极,细胞的周边完全形成网状,在网孔的周围有许多圆球形颗粒。这些结构特点提示,内胚层细胞以胚盘区为中心逐渐迁移至植物极。直径为9mm 胚泡的胚盘区,外表面已暴露出胚胎的外胚层细胞,细胞表面有短小的微绒毛,原条处的细胞表面微绒毛长而密集。胚盘区内面内胚层细胞的微绒毛多于外面。
On 10 days of pregnancy the blastocysts of 3 mm and 9 mm in diameters were
flushed out from the uterine horns of the Du-Chang-Ha and Dong-Bei-Min pigs.
The blastocysts were divided into four parts,that is the embryonic disc,the animal
pole,the lateral part and the vegetal pole.The outer and inner surface of the four
parts were observed with SEM and the findings are as follows:
1,The 3 mm blastocysts
The outer surface of the embryonic disc was still covered with trophoblastic
cells.Three kinds of cells can be discerned:the cell with round prominences and
long microvilli(MV);the cell with thin and long MV,the cell with smooth sur-
face.The trophoblast cells in other areas of the blastocyst were similar but slightly
flat.
The inner surface of the blactocyst consists of endoderm cells which were
different in the four parts.From the embryonic disc to the vegetal pole,the surface
structure of the endoderm cells changed regularly from small to large from dome-
shaped to flat and the distance between nuclei increased gradually.The MVs on the
cell surface:became less.These findings suggested that endoderm cells were
moving from the center of the embryonic disc to the vegetal pole.There were
many holes on the marginal area of the cells.The edge of the cell on the inner
surface of the vegetal pole forms a network.Many round granules can be seen in
the holes of the network.Their function may be for the transport of nutrients.
2,The 9 mm blastocysts
The outer surface of the embryonic disc was not covered with trophobla-
stic cells but covered with ectoderm cells.The ectoderm cells in the primitive
streak had long MV on their surface but short ones on other areas of the disc.
The inner surface of the embryonic disc was endoderm cells.The MVs on the
endoderm cells was much more numerous than the MVs on the ectoderm cells.The
differentiation of the cells in the pig blastocyst was also discussed.
出处
《解剖学报》
CAS
CSCD
北大核心
1989年第1期89-93,共5页
Acta Anatomica Sinica
