Dominant bovine ovarian follicular cysts express increased levels of messenger RNAs for luteinizing hormone receptor and 3 beta-hydroxysteroid dehydrogenase Delta(4),Delta(5) isomerase compared to normal dominant follicles

The objective was to compare ovarian steroids and expression of mRNAs encod ing cytochrome P450 side-chain cleavage, cytochrome P450 17 alpha -hydroxyl ase, cytochrome P450 aromatase, 3 beta -hydroxysteroid dehydrogenase Delta (4), Delta (5) isomerase, LH, and FSH receptors and estrogen receptor-beta in ovaries of cows with dominant and nondominant ovarian follicular cysts a nd in normal dominant follicles. Estradiol-17 beta, progesterone, and andro stenedione concentrations were determined in follicular fluid using specifi c RIAs. Dominant cysts were larger than young cysts or dominant follicles, whereas nondominant cysts were intermediate. Estradiol-17 beta (ng/ml) and total steroids (ng/follicle) were higher in dominant cysts than in dominant follicles. Expression of LH receptor and 3 beta -hydroxysteroid dehydrogen ase mRNAs was higher in granulosa cells of dominant cysts than in dominant follicles. Nondominant cysts had higher follicular concentrations of proges terone, lower estradiol-17 beta concentrations, and lower expression of ste roidogenic enzyme, gonadotropin receptor, and estrogen receptor-beta mRNAs than other groups. In summary, increased expression of LH receptor and 3 be ta -hydroxysteroid dehydrogenase mRNAs in granulosa and increased follicula r estradiol-17 beta concentrations were associated with dominant cysts comp ared to dominant follicles. Study of cysts at known developmental stages is useful in identifying alterations in follicular steroidogenesis.