Reproduction Abstracts

Upon sperm entry within the oocyte, pulsatile calcium release occurs, facilitating activation of the oocyte. While calcium signalling has been characterised in mouse oocytes, patterns within the whole cumulus oocyte complex (COC) and in larger mammals such as cow, are yet to be determined. The aim of this study was to investigate calcium changes in media, cumulus and oocytes during in vitro fertilisation in cattle oocytes.Cattle COCs were insemi...

Obesity in females causes altered fetal growth during pregnancy and permanently ‘programs’ the metabolism of offspring; however the origin of these changes and whether they are reversible is not known. We now show that in obese female mice the oocytes exhibit endoplasmic reticulum (ER) stress, high levels of intracellular lipid, reduced Ptx3 matrix production and fail to ovulate. The oocytes from obese mice contain normal levels of mtDNA but have reduced mitochondria...

Introduction: Recent studies indicate that dietary habits and hyperandrogenemia influence ovarian function in women. However, data are limited regarding the effects of western-style diet (WSD) and androgen (e.g. T) on follicle development, especially during the early follicular stage, in primates. The current study investigated the impact of WSD alone and with chronic T exposure on gene expression in small antral follicles (SAFs) of macaques.Materials an...

Introduction: It is understood that active agents in seminal fluid are key to initiating and coordinating mating-induced immunomodulation. This study aimed to characterise the structure of a network of cytokines whose interactions are thought to underpin this process in rats and mice.Methods: Seminal fluid, collected from isolated seminal glands, and serum, collected by cardiac puncture, were obtained from sexually mature Wistar rats (n=20) and ...

Introduction: Implantation is a highly coordinated event in which the receptive endometrium is primed to receive adhesion-competent blastocysts. Implantation relies on the bridging of integrins on the endometrium and the blastocyst by extracellular matrix proteins, such as fibronectin. Factors produced in the female reproductive tract are thought to support development of the blastocyst to an adhesion competent state and to ensure coordination of blastocyst implantation abilit...

Introduction: Peptide-YY (PYY) is a satiety hormone secreted by the colon. We have previously shown that PYY significantly increases in early lactation in rats, despite hyperphagia. Increased PYY may be associated with significantly increased gut growth by late lactation in dams with average-sized litters. Our aim was to determine whether feeding different litter sizes influences postpartum changes occurring during the maternal adaptation to lactation.Ma...

The prevalence of childhood allergic disease has increased dramatically in developed countries. Modern environmental changes are hypothesised to be causing deviations in fetal programming, in which the placenta plays a central role, increasing the prevalence of disease. We hypothesised that susceptibility to childhood allergy is determined by changes in placental function that programs fetal immune function. In this study we aimed to identify candidate genes and pathways in hu...

Introduction: During implantation, uterine luminal epithelial cells (UECs) disassemble cell–cell and cell–matrix adhesions that contribute to the formation of an epithelial barrier, which is refractory to blastocyst implantation. These changes are critical for successful implantation. We have shown previously that claudin 7 is present in UECs and is lost prior to implantation in the rat. Epithelial cell adhesion molecule (EpCAM) is another protein frequently associat...

Introduction: Pregnancy and lactation result in increasing maternal appetite and adiposity, which in humans may lead to long-term weight retention. Previous studies in this area are limited, but some suggest that the appetite-inhibiting (anorexigenic) gut hormone peptide-YY (PYY) is increased in lactation, despite hyperphagia. This work characterised changes in orexigenic (appetite-stimulating) ghrelin and anorexigenic PYY and glucagon-like peptide 1 (GLP1) and gut architectur...

Introduction: Previous studies have established that litter size during lactation influences body size and adiposity in male rat pups, but female pups and appetite-regulatory hormones have not been studied in this way. Gastrointestinal hormones ghrelin and peptide-YY (PYY) have roles in appetite regulation: high ghrelin levels signal hunger high PYY levels signal satiety. Both hormones are also associated with altered body mass and body composition. Previous findings (SRF 2014...