Regulatory mechanisms for natriuretic peptide signalling in sheep granulosa cells.

Natriuretic peptides (NPs) have been reported to have critical roles in follicular development and oocyte maturation in rodents. This study aimed to extend our current understanding of NP-mediated signalling pathways and mechanisms of action in the follicles of a monovulatory species. Ovine granulosa cells (GCs) and theca cells (TCs) were cultured under conditions designed to allow gonadotrophin-stimulated cell differentiation.

Steroids and miRNAs in assessment of ovarian tissue damage following cryopreservation.

Ovarian cortical tissue cryopreservation is a relatively novel approach to preserving fertility in women diagnosed with cancer. However, the effects of freezing-thawing are not fully understood, mainly due to the lack of suitable methods to assess tissue's survival after thawing. Disparities in steroid production have been associated with ovarian failure by disrupting folliculogenesis, ovulation and oocyte apoptosis.

Embryo cell allocation patterns are not altered by biopsy but can be linked with further development.

It has been suggested that first embryo cleavage can be related with the embryonic-abembryonic axis at blastocyst stage in mice. Thus, cells of the 2-cell embryo might be already biased to form the inner cell mass or trophectoderm. This study was conducted to observe the possible effects of embryo biopsy on cell allocation patterns during embryo preimplantation in two different mouse strains and the effects of these patterns on further development.

Pre-translational regulation of luteinizing hormone receptor in follicular somatic cells of cattle.

Differential regulation of LHR in theca cells (TC) and granulosa cells (GC) is important for normal follicular development. Unlike TC, GC only acquire LH-responsiveness during the later stages of antral follicle development. This study tested the hypothesis that differential LH-responsiveness in these two cell types may be due, in part, to shifts in cellular patterns of alternatively spliced LHR mRNA transcripts which may not be obvious from analysis of total LHR gene expression.

Cell density-mediated pericellular hypoxia and the local dynamic regulation of VEGF-a splice variants in ovine ovarian granulosa cells.

The primary aims of this study were to utilize a specialized culture system to further elucidate the functional significance of pericellular hypoxia within the granulosa cell (GC) compartment of growing follicles, and to clarify its effects on the production of vascular endothelial growth factor (VEGF)-A isoforms and steroid hormones. Multilaminar clusters formed rapidly in ovine GCs seeded at high density (HD), and Hypoxyprobe-1 protein adducts appeared markedly more abundant and HIF-1 activation significantly (P < 0.001) greater than in cells seeded at low density (LD).