Yonsei Med J.  1977 Jun;18(1):19-28. 10.3349/ymj.1977.18.1.19.

Electron Microscopic Studies of Mouse Oocytes and Two-cell Embryos exposed to Progesterone in Vitro

• Kwon HB
• Chung SO
• Deung YK
• Cho WK

• KMID: 687730
• DOI: http://doi.org/10.3349/ymj.1977.18.1.19

Abstract

This experiment was undertaken in order to find out if there is any morphological change in oocytes and two-cell embryos whose development have been suppressed by progesterone for six hours in vitro. It can be observed that some part of the outer side of nuclear membrane of the suppressed oocytes was damaged. The number of nuclear pores has decreased in suppressed oocytes and this suggests that progesterone might suppress the transport of intermediary metabolites between cytoplasm and nucleus. Sometimes, closely packed aggregates of parallel or irregular endoplasmic reticula were observed in suppressed oocytes. Microvilli of suppresed oocytes showed signs of degradation and the perivitelline space became apparent. Thus it is presumed that the egg membrane has constricted during cultivation under progesterone in vitro. The other cell organelles such as mitochondria, multivesicular bodies, cortical granules and fibrillar lattices showed no difference in morphology between treated and control (intact) oocytes. In two-cell embryos, there was also no evident morphological change except for the fact that many vacuoles appeared clearly in suppressed embryonal cells. In brief, there was no fundamental morphological change in the oocytes and the embryonal cells exposed to progesterone for six hours even though it inhibits their development. The action of progesterone should be investigated thoroughly.

MeSH Terms

Animal
Embryo/cytology*
Embryo/drug effects
Female
In Vitro
Mice
Oocytes/drug effects
Oocytes/ultrastructure*
Ovum/ultrastructure*
Progesterone/pharmacology*