| Description: | As the secondary follicle grows under the influence of FSH and
increases in size, fluid (follicular liquor) accumulates between the
granulosa cells. The fluid-filled spaces become confluent and form one
large space known as the antrum. Protein in the follicular liquid
sometimes is preserved in tissue processing and will give a background
stain. The oocyte is surrounded by several layers of granulosa cells
and is attached to the "wall" of the follicle by a clump of granulosa
cells known as cumulus oophorus. In this micrograph the oocyte has
detached from the mural cells and appears to be floating free in the
antrum, still surrounded by the granulosa cells (corona radiata). The
thecal cells outside the basal lamina of the granulosa cells have
differentiated into an inner theca interna (paler, larger cells) and a
theca externa (looks like the regular stroma). PK1460. Original mag.
50x H&E Secondary follicle. Cortex. Ovary. Female Reproductive
System. Cat. |