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Updated: Aug 29, 2026

Gene Expression Analyses in Human Follicles
Published on: February 17, 2023
Expression and distribution of cyclooxygenase-2 in human ovary during follicular development
Osamu Tokuyama1, Yoshiro Nakamura, Ayako Musoh
1Department of Obstetrics and Gynecology, Osaka City University Medical School, Japan. otoku@med.osaka-cu.ac.jp
Abstract:
Prostaglandins play important roles for oocyte maturation and follicular rupture. Cyclooxygenase-2 (COX-2), an inducible isoform of a prostaglandin metabolic enzyme, is essential for the timed production of prostaglandins in the ovary. The aim of the present study is to examine expression and distribution of COX-2 in human ovarian follicles at each of the maturation stages. Immunohistochemical staining shows that COX-2 is expressed in the granulosa cell layer of secondary and developing follicles, but is not detected in primary and Graafian follicles. Western blotting analysis revealed the existence of COX-2 in periovulatory follicular fluid at a mean concentration of 5.6 +/- 0.6 ng/ml. COX-2 might begin to be produced at the secondary follicle stage, and once a follicle reaches the Graafian follicle stage, the production of this enzyme is stopped. After exposure to luteinizing hormone (LH) surge, follicles might resume production of COX-2, and this is secreted into the follicular fluid.
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