atretic follicle

The average diameter of developing and atretic follicles within groups was similar (data not shown).

Mean diameters of developing and atretic follicles per individual animal were the basis for comparison between groups.

One of these females had 3 atretic follicles and the other had 6 developing follicles.

In atretic follicles BMP-3b mRNA expression was undetectable (Fig.

Unlike healthy follicles, BMP-4 mRNA was very low or undetectable in atretic follicles.

Finally the highest levels of BMP-2 mRNA in the ovary were seen in the GC of atretic follicles (Fig.

Cells in atretic follicles (GC and oocyte) continued to show high expression of BMPR-IB mRNA (Fig.

Atretic follicles were identified by the presence of 5 or more pyknotic nuclei in granulosa cells, leukocytes in the antrum, and loosening or degeneration of the mural layer of granulosa cells.

This, together with the failure to detect BMP-4 and 7 in the theca of atretic follicles, supports the idea that the cellular sites and coordinate expression of these BMP genes may have important regulatory roles in maintaining folliculogenesis.