The functional activity of cells from preovulatory follicles of hens (Gallus domesticus L.) under influence of triiodothyronine in vitro

Thyroid hormones have pleiotropic effects in vertebrates, regulating the growth, development and function of many organs, including those belonging to the reproductive system. Thyroid hormones may also be involved in regulating early ovarian aging and maintaining the supply of ovarian follicles. In the ovarian follicles of birds, including chickens, components of the thyroid system were found that ensure the implementation of the regulatory effects of thyroid hormones on the target cells. We performed for the first time a comparative analysis of the proliferative and steroidogenic activity of cultured granulosa and theca cells from the two most mature preovulatory follicles in Hisex White laying hens of different ages and reproductive statuses under the influence of triiodothyronine (T3), the most biologically active thyroid hormone. The purpose of the work was to examine in vitro the effect of T3 on the functional activity of cells from preovulatory follicles of the domestic hen (Gallus domesticus L.) in connection with the process of reproductive aging. Young hens aged 27-34 weeks with a long laying cycle (n = 6) and reproductively aged birds aged 74-94 weeks with a short laying cycle (n = 6) were used in the experiments. Granulosa and theca cells were isolated from the two largest yellow follicles F1 and F2. The follicular cells were cultured in medium containing 3 % fetal bovine serum for 48 h (granulosa) or 96 h (theca) in the absence (control) or presence of T3 at various concentrations (0.5-8.0 ng/ml). After culturing in the media, the concentration of sex steroid hormones was determined by ELISA or the proliferative activity of the cells was assessed by the photocolorimetric method using the CCK-8 reagent. In young hens, T3 at a concentration of 1.0-8.0 ng/ml increased 1.1-1.2 times (p function show_eabstract() { $('#eabstract1').hide(); $('#eabstract2').show(); $('#eabstract_expand').hide(); }