Korean J Obstet Gynecol.  2011 Jun;54(6):294-299. 10.5468/KJOG.2011.54.6.294.

Histologic comparison of polycystic ovary syndrome induced by estradiol valerate and letrozole

• Lim SC
• Jeong MJ
• Kim SE
• Kim SH
• Kim SC
• Seo SY
• Kim T
• Kang SS
• Bae CS

• KMID: 2274037
• DOI: http://doi.org/10.5468/KJOG.2011.54.6.294

Abstract

OBJECTIVE
To compare ovarian morphology of the estradiol valerate (EV)- and the letrozole (LE)-induced polycystic ovary syndrome (PCOS) in rat models.
METHODS
EV were injected (IM) to 10 Sprague-Dawley rats and LE were administered (PO) to the other 10 Sprague-Dawley rats for 21 days. Sixty days after single injection of EV and 21 days after LE administration, the animals were sacrificed and the ovaries were sectioned, measured and analyzed histopathologically.
RESULTS
LE-treated group showed larger ovary bearing more abundant cystic follicles with luteinized theca cells. These findings were more similar to human PCOS ovarian morphology.
CONCLUSION
LE-induced PCOS model is recommended to conduct PCOS-related animal experiments.

Keyword

Polycystic ovary syndrome; Estradiol valerate; Letrozole; Ovary

MeSH Terms

Animal Experimentation
Animals
Estradiol
Female
Humans
Lutein
Nitriles
Ovary
Polycystic Ovary Syndrome
Rats
Rats, Sprague-Dawley
Theca Cells
Triazoles
Ursidae
Estradiol
Lutein
Nitriles
Triazoles

Figure

• 

  Fig. 1 Scan image of the ovary, estradiol valerate-treated group. Relatively small ovary bearing four cystic follicles (asterisks) in the cortex is demonstrated (H&E, ×40).

• 

  Fig. 2 Higher magnification of the ovary, estradiol valerate-treated group. Two cystic follicles (asterisks) devoid of luteinized theca cells and stromal hyperthecosis (arrows) are identified. Neither corpus luteum nor corpus albicans are found (H&E, ×100).

• 

  Fig. 3 Scan image of the ovary, letrozole-treated group. Relatively large ovary bearing many cystic follicles (asterisks) in the thickened cortex (H&E, ×40).

• 

  Fig. 4 Higher magnification of the ovary, letrozole-treated group. Many cystic follicles (asterisks) consisted of luteinized theca cells are noted. A corpus luteum (pyramid) is demonstrated (H&E, ×100).

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