Changes in the Distribution of Endoplasmic Reticulum in Porcine Oocytes during Meiotic Maturation

成熟時における豚卵子の小胞体分布変化

Maeda Teruo

Yagyu Tetsuki

Journal of mammalian ova research = 日本哺乳動物卵子学会誌

Changes in the distribution of endoplasmic reticulum (ER) in porcine oocytes during meiotic maturation were examined. In the Germinal Vesicle (GV) stage oocyte, there were many bright clusters of ER present in the peripheral cytoplasm, and some of them formed a mass. This mass was absent in the Prometaphase I (Pro-MI) and Metaphase I (MI) stage oocytes, and the clusters became fewer than in the GV stage oocyte. ER accumulations that appear to be generated by scattering of the cluster or the mass were uniformly distributed in the peripheral cytoplasm and formed a thin layer beneath the plasma membrane. In the Metaphase II (MII) stage oocyte, the layer became more evident and wider, and a space with a relatively sparser distribution of ER was observed beneath the layer. From these results, it is clear that the distribution in the ER of porcine oocytes is changing during miotic maturation.

成熟時における豚卵子の小胞体分布変化を検討した. 卵核胞期(GV)の卵子では, 表層部に小胞体の集合体が多数観察され, 一部は固まり状を呈していた. 第一次減数分裂前中期(Pro-MI)及び中期(MI)の卵子では, その固まり状のものは消失し, 集合体数もGV期卵子と比較して減少していた. また, 小胞体の集合体あるいは集合体の固まり状のものが卵子表層部に均一に分散し, 細胞膜の内側に薄い層を形成していた. 第二減数分裂中期(MII)の卵子では, その層はより明瞭になり, 厚さを増していた. またその層の内側には小胞体の分布が少ない空間が認められた. 以上の結果より, 豚卵子においては成熟に伴って小胞体の分布が顕著に変化することが明らかとなった。

Endoplasmic reticulum

Porcine oocyte

Meiotic maturation

小胞体

豚卵子

減数分裂

Zoology [ 480 ]

eng

日本哺乳動物卵子学会

[ISSN] 1341-7738

[DOI] 10.1274/jmor.14.175

[NCID] AN10548943

[DOI] http://dx.doi.org/10.1274/jmor.14.175