Light and electron microscopic studies were undertaken to elucidate the structural changes of cumulus cells from the dispersed cumulus-oocyte complexes. Cumulus dispersion were induced by culturing porcine cumulus-oocyte complexes in the medium supplemented with FSH for 48hrs.
The results were summarized as follows
1. In intact porcine cumulus-oocyte complexes, shape of cumulus cells were round or ellipsoid but in the complexes treated with FSH, shape of cumulus cells were irregular and have well-developed cytoplasm processes.
2. In FSH-stimulated complexes, light and electron microscopic findings revealed that the cumulus cells were dettached from the zona pellucida surrounding the oocyte, intercellular space between cumulus cells became wide and junctions between them were disappeared.
3. Dispersed cumulus cells showed a remarkable increase of the smooth endoplasmic reticulum, a reduced number of rough endoplasmic reticulum, well-developed Golgi apparatus around the nucleus, and numerous lipid droplets which are variable in size and shape.
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