Expression and localisation of Bcl-2 and Bax proteins in developing rat ovary

• Published in: Research in veterinary science 2008-02, Vol.84 (1), p.56-61
• Main Authors: Gürsoy, E., Ergin, K., Başaloğlu, H., Koca, Y., Seyrek, K.
• Format: Article
• Language: English
• Subjects: Aging - metabolism; animal age; animal physiology; animal proteins; Animals; Animals, Newborn; Apoptosis; Atresia; Bax proteins; Bcl-2 proteins; bcl-2-Associated X Protein - analysis; bcl-2-Associated X Protein - metabolism; biochemical mechanisms; biological development; cell biology; differential staining; Enzymes; Female; females; follicular atresia; Gene Expression Regulation; granulosa cells; Histochemistry; luteal cells; Medical research; ovarian follicles; Ovary; Ovary - growth & development; Ovary - metabolism; physiological regulation; protein synthesis; Protein Transport; Proteins; Proto-Oncogene Proteins c-bcl-2 - analysis; Proto-Oncogene Proteins c-bcl-2 - metabolism; Rats; Rodents; Studies; tissue analysis; Veterinary medicine
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2007.04.006

Bcl-2 and Bax proteins localised mainly in granulosa cells. Primordial and primary follicles of new born rat ovary showed an intensive nuclear staining for Bax but faint staining for Bcl-2. In terms of staining intensity, no remarkable difference was observed within the same stage of developing follicle. Compared to new born rats, granulosa cells of adult and one month old rat ovary showed an increased staining both for Bcl-2 and Bax proteins. No staining was observed in primordial follicles of one month old and adult rats. However, granulosa cells of primary follicles, granulosa cells and theca cells in tertiary follicles of adult rat ovary also showed a strong staining for Bcl-2 and Bax proteins. Oocytes of follicles from different developmental stages revealed an apparent staining both for Bcl-2 and Bax proteins. However, in the more mature follicles oocytes stained more intensively. In developing corpus luteum a remarkable staining was observed for Bax. However, the staining was more prominent in regressing corpus luteum. Contrary to this, Bcl-2 stained the luteal cells in developing corpus luteum strongly, while in the fully developed corpus luteum no staining for Bcl-2 was observed. In conclusion, there was an apparent relation between the expression of the apoptosis regulating protein Bcl-2 and Bax and follicular development. Thus, during the follicular development Bcl-2 and Bax may be involved in granulosa cell demise in rat ovary. Furthermore, increased levels of Bax and decreased levels of Bcl-2 in the fully developed corpus luteum suggest that Bax plays a role in apoptosis of luteal cells in rat ovary.