Structure and Steroidogenic Activity of the Granulosa Layer of F1 Preovulatory Ovarian Follicles of the Hen (Gallus domesticus)

Abstract

WOJTYSIAK D., OKÓLSKI A., SECHMAN A. 2011. Structure and steroidogenic activity of the granulosa layer of F1 preovulatory ovarian follicles of the hen (Gallus domesticus). Folia biologica (Kraków) 59: 59-64. The study was performed to determine the structure and steroidogenic activity of granulosa cells derived from the germinal disc region, proximal region and distal region of the largest preovulatory ovarian follicle (F1) of the hen. The study was carried out on 34 Hy-Line Brown egg-laying hens aged 40 weeks. Morphology of the granulosa cells was studied by histological assessment and scanning electron microscopy. Moreover, the level of P " , histochemical activity of 3â-HSD and expression of 3â-HSD gene mRNA in granulosa cells of F1 follicle were determined. The findings indicate that the morphology and steroidogenic activity of the granulosa layer in F1 preovulatory ovarian follicle are associated with the region of the follicle. This is consistent with earlier studies. In the germinal disc region the granulosa cells form a multilayer while in the proximal and distal regions granulosa cells form a single layer. Analysis of P " concentration revealed that its level in granulosa cells was markedly reduced closer to the germinal disc. Moreover, our study demonstrates for the first time the lower histochemical activity of 3â-HSD and expression of 3â-HSD mRNA in granulosa cells from the germinal disc region compared with the proximal and distal region.

The comprehensive mechanisms underlying nonhierarchical follicular development in geese (Anser cygnoides)

“…The cell layers are primarily responsible for the transport of nutrients, mechanical support of growing oocytes, and the biosynthesis of steroids, which are important for regulating the rapid growth of follicles (Guraya, 1989;Wojtysiak et al, 2011;Rodler and Sinowatz, 2013). Recent data have further confirmed that the follicle wall secretes immunity peptides (Abdelsalam et al, 2010) and determines the fate of follicles, advancing in development or undergoing atresia (Quirk et al, 2004).…”

Histological and Developmental Study of Prehierarchical Follicles in Geese

“…All elements of the follicular wall undergo obvious structural changes during the phase of growth when observed under an electron microscope (KOVASC et al 1992;MADEKUROZWA & KIMARO 2006). The normal maturation process of the oocyte within the ovarian follicle depends on the coordinated development of the follicular wall inducing granulosa and theca cells under the influences of various hormones and growth factors (WOJTYSIAK et al 2011;LIN et al 2011;HRABIA et al 2008;ONAGBESAN et al 2009;SECHMAN 2013). The reproductive axis hormone, follicle-stimulating hormone (FSH), plays a pivotal role in the process of follicular development.…”

“…All these circumambient structures constitute the follicle wall. It can provide mechanical support and transport nutrients for the growing oocytes and play a key role in the synthesis of steroid hormones (WOJTYSIAK & KAPKOWSKA 2005;HERNANDEZ & BAHR 2003;WOJTYSIAK et al 2011), and it can also play important roles for the development of the oocyte and ovulation. All elements of the follicular wall undergo obvious structural changes during the phase of growth when observed under an electron microscope (KOVASC et al 1992;MADEKUROZWA & KIMARO 2006).…”

CircRNA Expression in Chicken Granulosa Cells Illuminated with Red Light

“…Moreover, host genes of DE circRNAs were enriched in ovarian steroidogenesis, as well as MAPK signalling, prolactin signalling and PI3K-Akt signalling pathways. Previous studies concluded that ovarian steroidogenesis is important for GC differentiation and follicle development [12,[34][35]. MAPK signalling prevents premature differentiation of the granulosa layer within prehierarchical follicles [36], which is involved in the regulation of follicle growth.…”