Medicine and Health Sciences Commons^™

Expression And Localization Of Nrf2/Keap1 Signalling Pathway Genes In Mouse Preimplantation Embryos Exposed To Free Fatty Acids., Grace Dionne, Michele D. Calder, Dean H Betts, Basim Abu Rafea, Andrew J Watson

Obstetrics & Gynaecology Publications

Obese women experience greater incidence of infertility, with reproductive tracts exposing preimplantation embryos to elevated free fatty acids (FFA) such as palmitic acid (PA) and oleic acid (OA). PA treatment impairs mouse preimplantation development in vitro, while OA co-treatment rescues blastocyst development of PA treated embryos. In the present study, we investigated the effects of PA and OA treatment on NRF2/Keap1 localization, and relative antioxidant enzyme (Glutathione peroxidase; Gpx1, Catalase; Cat, Superoxide dismutase; Sod1 and γ-Glutamylcysteine ligase catalytic unit; Gclc) mRNA levels, during in vitro mouse preimplantation embryo development. Female mice were superovulated, mated, and embryos cultured in the presence …

Gestational Age Impacts Birth To Placental Weight Ratio And Umbilical Cord Oxygen Values With Implications For The Fetal Oxygen Margin Of Safety, Bryan S Richardson, Barbra De Vrijer, Hilary K Brown, Larry Stitt, Sheryl Choo, Timothy R H Regnault

Obstetrics & Gynaecology Publications

Background: We determined the impact of gestational age (GA) from near term to term to post-term on birth/placental weight ratio and cord oxygen values with implications for placental transport efficiency for oxygen, fetal O2 consumption relative to delivery or fractional O2 extraction, and oxygen margin of safety.

Materials and methods: A hospital database was used to obtain birth/placental weight ratios, cord PO2 and other information on patients delivering between Jan 1, 1990 and Jun 15, 2011 with GA > 34 completed weeks (N=69,852). Oxygen saturation was calculated from the cord PO2 and pH data, while fractional O2 extraction was calculated from …

Structural Distress: Experiences Of Moral Distress Related To Structural Stigma During The Covid-19 Pandemic, Javeed Sukhera, Chetana Kulkarni, Taryn Taylor

Obstetrics & Gynaecology Publications

INTRODUCTION: The COVID-19 pandemic has taken a significant toll on the health of structurally vulnerable patient populations as well as healthcare workers. The concepts of structural stigma and moral distress are important and interrelated, yet rarely explored or researched in medical education. Structural stigma refers to how discrimination towards certain groups is enacted through policy and practice. Moral distress describes the tension and conflict that health workers experience when they are unable to fulfil their duties due to circumstances outside of their control. In this study, the authors explored how resident physicians perceive moral distress in relation to structural stigma. …

Water-Fat Magnetic Resonance Imaging Of Adipose Tissue Compartments In The Normal Third Trimester Fetus, Stephanie A Giza, Tianna L Koreman, Simran Sethi, Michael R Miller, Debbie A Penava, Genevieve D Eastabrook, Charles A Mckenzie, Barbra De Vrijer

Obstetrics & Gynaecology Publications

BACKGROUND: Assessment of fetal adipose tissue gives information about the future metabolic health of an individual, with evidence that the development of this tissue has regional heterogeneity.

OBJECTIVE: To assess differences in the proton density fat fraction (PDFF) between fetal adipose tissue compartments in the third trimester using water-fat magnetic resonance imaging (MRI).

MATERIALS AND METHODS: Water-fat MRI was performed in a 1.5-T scanner. Fetal adipose tissue was segmented into cheeks, thorax, abdomen, upper arms, forearms, thighs and lower legs. PDFF and R2* values were measured in each compartment.

RESULTS: Twenty-eight women with singleton pregnancies were imaged between 28 and …

Effects Of Maternal Obesity And Gestational Diabetes Mellitus On The Placenta: Current Knowledge And Targets For Therapeutic Interventions, Samantha Bedell, Janine Hutson, Barbra De Vrijer, Genevieve Eastabrook

Obstetrics & Gynaecology Publications

Obesity and gestational diabetes mellitus (GDM) are becoming more common among pregnant women worldwide and are individually associated with a number of placenta-mediated obstetric complications, including preeclampsia, macrosomia, intrauterine growth restriction and stillbirth. The placenta serves several functions throughout pregnancy and is the main exchange site for the transfer of nutrients and gas from mother to fetus. In pregnancies complicated by maternal obesity or GDM, the placenta is exposed to environmental changes, such as increased inflammation and oxidative stress, dyslipidemia, and altered hormone levels. These changes can affect placental development and function and lead to abnormal fetal growth and development …

Maternal Obesity Reduces Placental Autophagy Marker Expression In Uncomplicated Pregnancies, Matthew Cohen, Emily Guo, Aidan Pucchio, Barbra De Vrijer, Trevor G Shepherd, Genevieve Eastabrook

Obstetrics & Gynaecology Publications

AIM: Obesity has been associated with changes in autophagy and its increasing prevalence among pregnant women is implicated in higher rates of placental-mediated complications of pregnancy such as pre-eclampsia and intrauterine growth restriction. Autophagy is involved in normal placentation, thus changes in autophagy may lead to impaired placental function and development. The aim of this study was to investigate the connection between obesity and autophagy in the placenta in otherwise uncomplicated pregnancies.

METHODS: Immunohistochemistry and western blot analysis were done on placental and omental samples from obese (body mass index [BMI] ≥30 kg/m

RESULTS: As pre-pregnancy BMI increased, there was …

Labour Progression In Obese Women: Are Women With Increased Body Mass Index Having Unnecessary Cesarean Sections?, Caroline Shenouda, Aloka Wijesooriya, Amanda Toufeili, Michael R Miller, Debbie Penava, Barbra De Vrijer

Obstetrics & Gynaecology Publications

OBJECTIVE: This study sought to determine whether obese pregnant women undergo cesarean sections without an adequate trial of labour. This may affect future birth and pregnancy outcomes.

METHODS: A retrospective analysis was done on 526 parturients at Victoria Hospital in London, Ontario. Women were categorized according to parity and pre-pregnancy body mass index (BMI; normal weight, BMI 18.5-24.9 kg/m

RESULTS: Obese class II and III primiparous women required an additional 1.62 and 2.67 hours (P = 0.012), respectively, to reach a dilation of 10 cm compared with their normal weight counterparts; obese class II and III multiparous women required an …

Perseverance, Faith And Stoicism: A Qualitative Study Of Medical Student Perspectives On Managing Fatigue, Taryn S Taylor, Alexandra L Raynard, Lorelei Lingard

Obstetrics & Gynaecology Publications

CONTEXT: Fatigue risk management (FRM) strategies offer a potential solution to the widespread problem of fatigued trainees in the clinical workplace. These strategies assume a shared perception that fatigue is hazardous. Despite the growing body of evidence suggesting that fatigue leads to burnout and medical errors, previous research suggests that residents perceive fatigue as a personal, surmountable burden rather than an occupational hazard. Before we can implement FRM, we need a better understanding of when and how such problematic notions of fatigue are adopted by medical trainees. Thus, we sought to explore how third-year medical students understand and manage the …

Implantation Failure In Female Kiss1-/- Mice Is Independent Of Their Hypogonadic State And Can Be Partially Rescued By Leukemia Inhibitory Factor., Michele Calder, Yee-Ming Chan, Renju Raj, Macarena Pampillo, Adrienne Elbert, Michelle Noonan, Carolina Gillio-Meina, Claudia Caligioni, Nathalie G Bérubé, Moshmi Bhattacharya, Andrew J Watson, Stephanie B Seminara, Andy V Babwah

Obstetrics & Gynaecology Publications

The hypothalamic kisspeptin signaling system is a major positive regulator of the reproductive neuroendocrine axis, and loss of Kiss1 in the mouse results in infertility, a condition generally attributed to its hypogonadotropic hypogonadism. We demonstrate that in Kiss1(-/-) female mice, acute replacement of gonadotropins and estradiol restores ovulation, mating, and fertilization; however, these mice are still unable to achieve pregnancy because embryos fail to implant. Progesterone treatment did not overcome this defect. Kiss1(+/-) embryos transferred to a wild-type female mouse can successfully implant, demonstrating the defect is due to maternal factors. Kisspeptin and its receptor are expressed in the mouse …

Stress-Inducible Phosphoprotein 1 Has Unique Cochaperone Activity During Development And Regulates Cellular Response To Ischemia Via The Prion Protein., Flavio H Beraldo, Iaci N Soares, Daniela F Goncalves, Jue Fan, Anu A Thomas, Tiago G Santos, Amro H Mohammad, Martin Roffé, Michele D Calder, Simona Nikolova, Glaucia N Hajj, Andre L Guimaraes, Andre R Massensini, Ian Welch, Dean H Betts, Robert Gros, Maria Drangova, Andrew J Watson, Robert Bartha, Vania F Prado, Vilma R Martins, Marco A M Prado

Obstetrics & Gynaecology Publications

Stress-inducible phosphoprotein 1 (STI1) is part of the chaperone machinery, but it also functions as an extracellular ligand for the prion protein. However, the physiological relevance of these STI1 activities in vivo is unknown. Here, we show that in the absence of embryonic STI1, several Hsp90 client proteins are decreased by 50%, although Hsp90 levels are unaffected. Mutant STI1 mice showed increased caspase-3 activation and 50% impairment in cellular proliferation. Moreover, placental disruption and lack of cellular viability were linked to embryonic death by E10.5 in STI1-mutant mice. Rescue of embryonic lethality in these mutants, by transgenic expression of the …

Endogenous Folate Accumulation In Oocytes And Preimplantation Embryos And Its Epigenetic Implications., Mellissa R W Mann, Andrew J Watson

Obstetrics & Gynaecology Publications

No abstract provided.

P38 Mapk Regulates Cavitation And Tight Junction Function In The Mouse Blastocyst., Christine E Bell, Andrew J Watson

Obstetrics & Gynaecology Publications

UNLABELLED: Blastocyst formation is essential for implantation and maintenance of pregnancy and is dependent on the expression and coordinated function of a series of proteins involved in establishing and maintaining the trans-trophectoderm ion gradient that enables blastocyst expansion. These consist of Na/K-ATPase, adherens junctions, tight junctions (TJ) and aquaporins (AQP). While their role in supporting blastocyst formation is established, the intracellular signaling pathways that coordinate their function is unclear. The p38 MAPK pathway plays a role in regulating these proteins in other cell types and is required for embryo development at the 8-16 cell stage, but its role has not …

Embryo Collection Induces Transient Activation Of Xbp1 Arm Of The Er Stress Response While Embryo Vitrification Does Not., Tamara Abraham, Christopher L Pin, Andrew J Watson

Obstetrics & Gynaecology Publications

Embryo cryopreservation has become a standard procedure in the practice of assisted reproduction. While routinely performed in IVF labs, the effects of embryo vitrification on the molecular mechanisms governing preimplantation development remain largely unknown. The endoplasmic reticulum stress (ER stress) response is an evolutionary conserved mechanism that cells employ to manage ER stress. ER stress can be defined as an imbalance between protein synthesis and secretion within the ER. The primary focus of this study was to investigate whether standard embryo manipulations, including embryo collection, culture and vitrification, result in activation of the ER stress pathway in vitro and to …

Outer Space And Oocyte Developmental Competence., Andrew J Watson

Obstetrics & Gynaecology Publications

No abstract provided.

Culture Medium, Gas Atmosphere And Mapk Inhibition Affect Regulation Of Rna-Binding Protein Targets During Mouse Preimplantation Development., Michele D Calder, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

During oogenesis, mammalian oocytes accumulate maternal mRNAs that support the embryo until embryonic genome activation. RNA-binding proteins (RBP) may regulate the stability and turnover of maternal and embryonic mRNAs. We hypothesised that varying embryo culture conditions, such as culture medium, oxygen tension and MAPK inhibition, affects regulation of RBPs and their targets during preimplantation development. STAU1, ELAVL1, KHSRP and ZFP36 proteins and mRNAs were detected throughout mouse preimplantation development, whereas Elavl2 mRNA decreased after the two-cell stage. Potential target mRNAs of RBP regulation, Gclc, Slc2a1 and Slc7a1 were detected during mouse preimplantation development. Gclc mRNA was significantly elevated in embryos …

Ouabain Stimulates A Na+/K+-Atpase-Mediated Sfk-Activated Signalling Pathway That Regulates Tight Junction Function In The Mouse Blastocyst., Holly Giannatselis, Michele Calder, Andrew J Watson

Obstetrics & Gynaecology Publications

The Na(+)/K(+)-ATPase plays a pivotal role during preimplantation development; it establishes a trans-epithelial ionic gradient that facilitates the formation of the fluid-filled blastocyst cavity, crucial for implantation and successful pregnancy. The Na(+)/K(+)-ATPase is also implicated in regulating tight junctions and cardiotonic steroid (CTS)-induced signal transduction via SRC. We investigated the expression of SRC family kinase (SFK) members, Src and Yes, during preimplantation development and determined whether SFK activity is required for blastocyst formation. Embryos were collected following super-ovulation of CD1 or MF1 female mice. RT-PCR was used to detect SFK mRNAs encoding Src and Yes throughout preimplantation development. SRC and …

Oocyte Peptides As Paracrine Tools For Ovarian Stimulation And Oocyte Maturation., David G Mottershead, Andrew J Watson

Obstetrics & Gynaecology Publications

Recent studies report the production and isolation of a stable bioactive recombinant human bone morphogenetic protein 15 (rhBMP15) that is appropriately processed in HEK-293 cells and activates the SMAD 1/5/8 pathway in mouse granulosa cell cultures. Further, the purified rhBMP15 induces the expression of genes associated with cumulus expansion. Thanks to recent research, we have a greater understanding of the importance of the dialogue that occurs between the oocyte and the granulosa cell layer with regard to regulating folliculogenesis and the acquisition of oocyte developmental competence and maturation. BMP15 is one of the critical components of these intra-follicular communication pathways. …

Mitogen-Activated Protein Kinase (Mapk) Pathways Mediate Embryonic Responses To Culture Medium Osmolarity By Regulating Aquaporin 3 And 9 Expression And Localization, As Well As Embryonic Apoptosis., Christine E Bell, Nathalie M K Larivière, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

BACKGROUND: In order to advance the development of culture conditions and increase the potential for supporting normal preimplantation embryo development in vitro, it is critical to define the mechanisms that early embryos utilize to survive in culture. We investigated the mechanisms that embryos employ in response to culture medium osmolarity. We hypothesized that mitogen-activated protein kinase (MAPK) pathways mediate responses to hyperosmotic stress by regulating Aquaporin (AQP) 3 and 9 expression as well as embryonic apoptosis.

METHODS: Real-time reverse transcription and polymerase chain reaction and whole-mount immunofluorescence were used to determine the relative mRNA levels and protein localization patterns of …

Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan

Obstetrics & Gynaecology Publications

Preimplantation development directs the formation of an implantation- or attachment-competent embryo so that metabolic interactions with the uterus can occur, pregnancy can be initiated, and fetal development can be sustained. The preimplantation embryo exhibits a form of autonomous development fueled by products provided by the oocyte and also from activation of the embryo's genome. Despite this autonomy, the preimplantation embryo is highly influenced by factors in the external environment and in extreme situations, such as those presented by embryo culture or nuclear transfer, the ability of the embryo to adapt to the changing environmental conditions or chromatin to become reprogrammed …

Pp2cdelta (Ppm1d, Wip1), An Endogenous Inhibitor Of P38 Mapk, Is Regulated Along With Trp53 And Cdkn2a Following P38 Mapk Inhibition During Mouse Preimplantation Development., Jenny A Hickson, Barry Fong, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

Preimplantation embryos utilize mitogen-activated protein kinase signaling (MAPK) pathways to relay signals from the external environment to prepare appropriate responses and adaptations to a changing milieu. It is therefore important to investigate how MAPK pathways are regulated during preimplantation development. This study was conducted to investigate whether PP2Cdelta (Ppm1d, WIP1) is expressed during mouse preimplantation development and to determine the influences of p38 MAPK inhibition on expression of Trp53 (p53), Ppm1d, (WIP1), and Cdkn2a (p16) during mouse preimplantation development. Our results indicate that Trp53, Ppm1d, and Cdkn2a mRNAs and TRP53 and PP2Cdelta proteins are expressed throughout mouse preimplantation development. Treatment …

Na/K-Atpase Beta1 Subunit Expression Is Required For Blastocyst Formation And Normal Assembly Of Trophectoderm Tight Junction-Associated Proteins., Pavneesh Madan, Keeley Rose, Andrew J Watson

Obstetrics & Gynaecology Publications

Na/K-ATPase plays an important role in mediating blastocyst formation. Despite the expression of multiple Na/K-ATPase alpha and beta isoforms during mouse preimplantation development, only the alpha1 and beta1 isoforms have been localized to the basolateral membrane regions of the trophectoderm. The aim of the present study was to selectively down-regulate the Na/K-ATPase beta1 subunit employing microinjection of mouse 1 cell zygotes with small interfering RNA (siRNA) oligos. Experiments comprised of non-injected controls and two groups microinjected with either Stealthtrade mark Na/K-ATPase beta1 subunit oligos or nonspecific Stealthtrade mark siRNA as control. Development to the 2-, 4-, 8-, and 16-cell and …

Oocyte Cytoplasmic Maturation: A Key Mediator Of Oocyte And Embryo Developmental Competence., A J Watson

Obstetrics & Gynaecology Publications

Efforts have intensified to successfully mature and inseminate oocytes in vitro and then culture ensuing embryos to transferable stages from a large number of mammalian species. Success varies, but generally even for the most successful species it is only possible to obtain a maximum of a 40 to 50% development of zygotes to the blastocyst stage. Reduced oocyte developmental competence is suggested as a primary reason for the reduced potential of in vitro-produced embryos. The vast majority of in vitro-matured oocytes are meiotically competent; however, many do not attain an optimal oocyte diameter before insemination. Variations in oocyte in vitro …

Mouse Preimplantation Embryo Responses To Culture Medium Osmolarity Include Increased Expression Of Ccm2 And P38 Mapk Activation., Barry Fong, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

BACKGROUND: Mechanisms that confer an ability to respond positively to environmental osmolarity are fundamental to ensuring embryo survival during the preimplantation period. Activation of p38 mitogen-activated protein kinase (MAPK) occurs following exposure to hyperosmotic treatment. Recently, a novel scaffolding protein called Osmosensing Scaffold for MEKK3 (OSM) was linked to p38 MAPK activation in response to sorbitol-induced hypertonicity. The human ortholog of OSM is cerebral cavernous malformation 2 (CCM2). The present study was conducted to investigate whether CCM2 is expressed during mouse preimplantation development and to determine whether this scaffolding protein is associated with p38 MAPK activation following exposure of preimplantation …

Na+/K+ -Atpase Regulates Tight Junction Formation And Function During Mouse Preimplantation Development., Michelle I Violette, Pavneesh Madan, Andrew J Watson

Obstetrics & Gynaecology Publications

Research applied to the early embryo is required to effectively treat human infertility and to understand the primary mechanisms controlling development to the blastocyst stage. The present study investigated whether the Na(+)/K(+)-ATPase regulates tight junction formation and function during blastocyst formation. To investigate this hypothesis, three experimental series were conducted. The first experiments defined the optimal dose and treatment time intervals for ouabain (a potent and specific inhibitor of the Na(+)/K(+)-ATPase) treatment. The results demonstrated that mouse embryos maintained a normal development to the blastocyst stage following a 6-h ouabain treatment. The second experiments investigated the effects of ouabain treatment …

P38 Mitogen-Activated Protein Kinase (Mapk) First Regulates Filamentous Actin At The 8-16-Cell Stage During Preimplantation Development., Andrew J M Paliga, David R Natale, Andrew J Watson

Obstetrics & Gynaecology Publications

BACKGROUND INFORMATION: The MAPK (mitogen-activated protein kinase) superfamily of proteins consists of four separate signalling cascades: the c-Jun N-terminal kinase or stress-activated protein kinases (JNK/SAPK); the ERKs (extracellular-signal-regulated kinases); the ERK5 or big MAPK1; and the p38 MAPK group of protein kinases, all of which are highly conserved. To date, our studies have focused on defining the role of the p38 MAPK pathway during preimplantation development. p38 MAPK regulates actin filament formation through the downstream kinases MAPKAPK2/3 (MAPK-activated protein kinase 2/3) or MAPKAPK5 [PRAK (p38 regulated/activated kinase)] and subsequently through HSP25/27 (heat-shock protein 25/27). We recently reported that 2-cell-stage murine …

Effect Of Serum And Cumulus Cell Expansion On Marker Gene Transcripts In Bovine Cumulus-Oocyte Complexes During Maturation In Vitro., Michele D Calder, Anita N Caveney, Marc-Andre Sirard, Andrew J Watson

Obstetrics & Gynaecology Publications

OBJECTIVE: To determine the distribution of transcripts encoding the FSH receptor (FSHr), LH receptor (LHr), connexin 43 (Cx43), cyclooxygenase-2 (COX-2), and prostaglandin E(2) receptors 2 and 3 (EP2 and EP3) within bovine cumulus-oocyte complexes (COCs) and denuded oocytes and investigate the influence of gonadotropins, serum, and cumulus cell expansion on the abundance of transcripts encoding these genes.

DESIGN: Prospective controlled animal study.

SETTING: University research laboratory.

PATIENT(S): Animal models for human studies.

INTERVENTION(S): Cumulus-oocyte complexes were treated in culture with serum and gonadotropin-supplemented media to examine the effects to mRNA transcript levels.

MAIN OUTCOME MEASURE(S): Variation in mRNA transcript levels. …

Deletion Of The Na/K-Atpase Alpha1-Subunit Gene (Atp1a1) Does Not Prevent Cavitation Of The Preimplantation Mouse Embryo., L C Barcroft, A E Moseley, J B Lingrel, A J Watson

Obstetrics & Gynaecology Publications

Increases in Na/K-ATPase activity occur concurrently with the onset of cavitation and are associated with increases in Na(+)-pump subunit mRNA and protein expression. We have hypothesized that the alpha1-isozyme of the Na/K-ATPase is required to mediate blastocyst formation. We have tested this hypothesis by characterizing preimplantation development in mice with a targeted disruption of the Na/K-ATPase alpha1-subunit (Atp1a1) using embryos acquired from matings between Atp1a1 heterozygous mice. Mouse embryos homozygous for a null mutation in the Na/K-ATPase alpha1-subunit gene are able to undergo compaction and cavitation. These findings demonstrate that trophectoderm transport mechanisms are maintained in the absence of the …

P38 Mapk Signaling During Murine Preimplantation Development., David R Natale, Andrew J M Paliga, Frank Beier, S J A D'Souza, Andrew J Watson

Obstetrics & Gynaecology Publications

Mitogen-activated protein kinase (MAPK) pathways mediate some important cellular processes and are likely to also regulate preimplantation development. The role of p38 MAP kinase signaling during murine preimplantation development was investigated in the present study. p38 MAPK, p38-regulated or -activated kinase (PRAK; MK5), map kinase-activated protein kinase 2 (MK2), and heat shock protein 25 (hsp25) mRNAs and proteins were detected throughout preimplantation development. Two-cell stage embryos cultured in the presence of SB220025 and SB203580 (specific inhibitors of p38 MAPK alpha/beta), progressed to the eight-cell stage with the same frequency as controls; however, treated embryos halted their development at the 8- …

A Null Mutation For Tissue Inhibitor Of Metalloproteinases-3 (Timp-3) Impairs Murine Bronchiole Branching Morphogenesis., Sean E Gill, M Cynthia Pape, Rama Khokha, Andrew J Watson, Kevin J Leco

Obstetrics & Gynaecology Publications

Tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) degradation by matrix metalloproteinases (MMPs). We have examined the role of TIMP-3 on ECM homeostasis and bronchiole branching morphogenesis during murine embryogenesis. Employing an in vitro organ culture system, we found decreased bronchiolar branching in null lungs when compared with wild type (WT) counterparts after 2 days in culture. When a synthetic inhibitor of MMPs at low dose was added to the culture system, branching was augmented regardless of genotype. Gelatin and in situ zymography revealed that null lungs exhibited enhanced activation of MMPs throughout lung development. We analysed the impact …

Responsiveness Of Bovine Cumulus-Oocyte-Complexes (Coc) To Porcine And Recombinant Human Fsh, And The Effect Of Coc Quality On Gonadotropin Receptor And Cx43 Marker Gene Mrnas During Maturation In Vitro., Michele D Calder, Anita N Caveney, Lawrence C Smith, Andrew J Watson

Obstetrics & Gynaecology Publications

Substantially less development to the blastocyst stage occurs in vitro than in vivo and this may be due to deficiencies in oocyte competence. Although a large proportion of bovine oocytes undergo spontaneous nuclear maturation, less is known about requirements for proper cytoplasmic maturation. Commonly, supraphysiological concentrations of FSH and LH are added to maturation media to improve cumulus expansion, fertilization and embryonic development. Therefore, various concentrations of porcine FSH (pFSH) and recombinant human FSH (rhFSH) were investigated for their effect on bovine cumulus expansion in vitro. Expression of FSHr, LHr and Cx43 mRNAs was determined in cumulus-oocyte complexes to determine …