Steroidogenic acute regulatory protein (StAR) transfers cholesterol from the outer to inner mitochondrial membrane initiate steroidogenesis. Our purpose was determine tissue distribution of StAR mRNA and occurrence gene products in bovine corpus luteum (CL). Tissues were taken slaughterhouse or by ovariectomy cattle at specific times after estrus ovulation. identified Northern analysis employing a 1.6-kb cDNA mouse probe, polyclonal antiserum against used Western luteal tissue. The for...

Some fibroblast growth factors (FGFs) affect ovarian follicle cell and/or differentiation. Whereas many FGFs activate several FGF receptors, FGF7 and FGF10 primarily only one, FGFR2B. As is produced by bovine theca cells acts on granulosa cells, we tested the hypothesis that may also play a role in folliculogenesis cattle. Reverse transcription-polymerase chain reaction demonstrated presence of mRNA oocytes antral follicles, as well preantral follicles. protein was detected...

Paracrine cell signaling is believed to be important for ovarian follicle development, and a role some members of the fibroblast growth factor (FGF) family has been suggested. In present study, we tested hypothesis that FGF-8 its cognate receptors (FGFR3c FGFR4) are expressed in bovine antral follicles. RT-PCR was used analyze Fgf8 , Fgfr3c Fgfr4 mRNA levels oocytes, granulosa theca cells. expression detected oocytes cells; this pattern differs from reported rodents. Granulosa cells, but not...

Oocyte-secreted factors (OSFs) regulate differentiation of cumulus cells and are pivotal relevance for fertility. Bone morphogenetic protein 15 (BMP15) fibroblast growth factor 10 (FGF10) OSFs enhance oocyte competence by unknown mechanisms. We tested the hypothesis that BMP15 FGF10, alone or combined in maturation medium, expansion expression genes preovulatory cascade glucose metabolism favouring hyaluronic acid production bovine cumulus-oocyte complexes (COCs). FGF10 increased percentage...

We determined 1) whether the previously observed induction of estradiol secretion in bovine granulosa cells cultured serum-free conditions is associated with an increase cytochrome P450 aromatase (P450arom) mRNA abundance and 2) P450arom levels are responsive to FSH vitro. Granulosa from small (2–4-mm) follicles were medium. Estradiol increased time culture was correlated abundance. Progesterone also culture, but cholesterol side-chain cleavage (P450scc) did not. stimulated abundance; effect...

The failure of anti-steroid treatments to induce multiple ovulations in cattle a repeatable way, prompted us examine the role gonadal steroids control gonadotropin secretion this species. A better understanding cow would assist development prolificacy. Groups six heifers were implanted with one three sizes estradiol (E2) implant on day 9 synchronized estrous cycle, and five received empty implants. All ovariectomized during luteal phase subsequent cycle given progesterone-releasing...

The aims of this study were to investigate whether treatment with a single ovulatory dose hCG, between the day oestrus and end luteal phase, could induce extra ovulations in heifers presence an existing corpus luteum (CL) affected response. Heifers (N = 32) injected 1500 i.u. hCG or saline on given oestrous cycle. Treatments repeated during subsequent cycles provide total 71 observations, 57 which followed injection Day 0 (oestrus) 16, 14 injections as controls. Ovulatory responses noted by...

Fibroblast growth factors (FGF) are involved in paracrine signaling between cell types the ovarian follicle. FGF8, for example, is secreted by oocytes and controls cumulus metabolism. The closely related FGF18 also expressed mice. objective of this study was to assess potential role follicle a monovulatory species, cow. Messenger RNA encoding detected primarily theca cells, contrast mouse, not bovine oocytes. Addition protein granulosa cultures inhibited estradiol progesterone secretion as...

Whereas the roles of canonical wingless-type MMTV (mouse mammary tumor virus) integration site family (WNT) signaling pathway in regulation ovarian follicle growth and steroidogenesis are now established, noncanonical WNT ovary has been largely overlooked. Noncanonical WNTs, including WNT5a WNT11, expressed granulosa cells (GCs) differentially regulated throughout development, but their physiologic remain unknown. Using conditional gene targeting, we found that GC-specific inactivation Wnt5a...

At the onset of lactation, dairy cattle are anestrous owing mainly to a state negative energy balance. Adipose tissue is mobilized meet demands milk production, and this alters secretion adipose-derived hormones, called adipokines. Irisin myokine/adipokine that may play role in fertility; plasma concentrations increase post-partum, irisin decreased progesterone estradiol from bovine granulosa cells vitro. To our knowledge, effects on theca cell function vitro follicle growth vivo have not...

The mechanosensing properties of endothelial cell-cell junctions are essential for vascular beds to respond the mechanical forces exerted by blood flow. In states disturbed flow, cells (ECs) become activated and transition a pro-inflammatory, atheroprone phenotype. Here, we investigated role transmembrane glycoprotein neuropilin 2 (NRP2) in maintaining adherens junction integrity using cultured immortalised mouse ECs genetically modified model demonstrate effects an endothelial-specific...

Abstract The objective was to analyze gene expression in bovine granulosa cells of the dominant follicle by mRNA differential display. Total RNA extracted from ≤4 mm follicles, day 5 (D5) and hCG‐induced preovulatory follicles. A differentially expressed cDNA observed group used screen a cell library, which resulted cloning 2,096 bp cDNA. Amino acid comparison showed identity level 91.4, 83.9, 83.1% when compared human, rat, mouse serine protease inhibitor E2, SERPINE2, also called...

Abstract We sought to determine whether risedronate can preserve cortical bone mass and mechanical properties during long-term disuse in dogs, assessed by histomorphometry biomechanics on metacarpal diaphyses. Risedronate slowed thinning partially preserved properties, but it was unable suppress loss the degree seen other osteoporoses. Introduction: Disuse induces dramatic resulting from greatly elevated osteoclastic resorption. Targeting osteoclasts with antiresorptive agents, such as...

The aim of these experiments was to determine whether the presence a dominant follicle affects developmental competence oocytes from small antral follicles cattle. In Expt 1, or follicular fluid samples were collected 2–7 mm in diameter before (day 3 oestrous cycle; n = 4) after (days 6 and 7 6) emergence first wave (verified by rectal ultrasonography). Five ten aspirated for determination individual concentrations oestradiol, progesterone, testosterone dimeric inhibin; remaining each cow...

Abstract In cattle, most evidence suggests that granulosa cells express LH receptors (LHR) after (or as) the follicle becomes dominant, however there is some suggestion from smaller pre‐dominant follicles may several LHR mRNA splice variants. The objective of this study was to measure expression in bovine defined size and steroidogenic ability, small (<6 mm diameter) undergoing differentiation vitro. Semiquantitative RT‐PCR demonstrated undetectable <7 diameter (nondominant follicles),...

Fibroblast growth factor 17 (FGF17) is a member of the FGF8 subfamily that appears to be relevant folliculogenesis and oogenesis, as prototype an oocyte-derived protein signals cumulus cells. has structural receptor-binding similarities FGF17, whose expression in ovary not been reported. In this study, we demonstrate localization FGF17 oocyte preantral follicles, granulosa cells antral follicles. Real-time PCR demonstrated presence mRNA oocytes and, lesser extent, theca abundance was low...

Survival and inhibitory factors regulate steroidogenesis determine the fate of developing follicles. The objective this study was to role transforming growth factor-β1 (TGFB1) in regulation estradiol-17β (E 2 ) progesterone (P 4 secretion FSH-stimulated bovine granulosa cells. Granulosa cells were obtained from 5 mm follicles cultured serum-free medium. FSH dose (1 10 ng/ml for 6 days) time culture (2, 4, days with 1 FSH) increased E mRNA expression -related enzymes cytochrome P450 aromatase...