CSIRO Publishing blank image blank image blank image blank imageBooksblank image blank image blank image blank imageJournalsblank image blank image blank image blank imageAbout Usblank image blank image blank image blank imageShopping Cartblank image blank image blank image You are here: Journals > Reproduction, Fertility and Development   
Reproduction, Fertility and Development
Journal Banner
  Vertebrate Reproductive Science & Technology
 
blank image Search
 
blank image blank image
blank image
 
  Advanced Search
   

Journal Home
About the Journal
Editorial Board
Contacts
Content
All Issues
Special Issues
Research Fronts
Sample Issue
For Authors
General Information
Instructions to Authors
Submit Article
Open Access
For Referees
Referee Guidelines
Review an Article
Annual Referee Index
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

blue arrow e-Alerts
blank image
Subscribe to our email Early Alert or RSS feeds for the latest journal papers.

red arrow Connect with us
blank image
facebook twitter youtube

red arrow Connect with SRB
blank image
facebook TwitterIcon

Affiliated Societies

RFD is the official journal of the International Embryo Transfer Society and the Society for Reproductive Biology.


 

Article << Previous     |     Next >>   Contents Vol 22(1)

356 MODULATION OF PORCINE NUCLEAR MATURATION STATUS USING A SPECIFIC PHOSPHODIESTERASE INHIBITOR

M. L. Sutton-McDowall A, R. B. Gilchrist A, J. G. Thompson A

IVF Vet Solutions & Robinson Institute, Research Centre for Reproductive Health, School of Paediatrics & Reproductive Health, The University of Adelaide, Adelaide, South Australia, Australia
 
 Export Citation
 Print
  


Abstract

Compared to other livestock species, IVM porcine COCs have poor developmental competence.Thisismost likely due to poor cytoplasmic maturation and asynchronous nuclear maturation. The resumption of nuclear maturation is largely regulated by cyclic adenosine monophosphate(cAMP), with increasing intra-oocyte levels prolonging cumulus-oocyte gap junction communication and delaying meiotic resumption. Modulation of cAMP levels using phosphodiesterase (PDE) inhibitors during bovine IVM significantly improves developmental competence (Thomas et al. 2004 Biol. Reprod. 71, 1142-1149). Hence, the aim of this study was to determine the effect of a type 3 PDE inhibitor (cilostamide, CIL) supplementation during porcine IVM on nuclear maturation, using a defined culture system. COCs derived from follicles of prepubertal gilts were cultured in groups of 10 in 100μL IVM medium (VitroMat, IVF Vet Solutions, Adelaide, Australia) +100 m IU mL-1 rhFSH +4 mg mL-1 BSA and nuclear maturation was assessed using orcein dye. Exp. 1: IVM medium was supplemented with 0, 5, 10, and 20 μM CIL or 0, 0.01, 0.1, 1, and 10 μM CIL and nuclear maturation was determined at 24 h and 44 h. Exp. 2: COCs were cultured in ± 0.1 μM CIL and nuclear maturation was assessed at 24 h, 44 h, 48 h, 52 h, and 56 h. Proportions of COCs at each stage of nuclear maturation were arcsine transformed and differences determined using a general linear model and Bonferroni post hoc test. Four replicates per experiment were performed with 20 COCs used for each treatment and/or time point. Results for Exp. 1 revealed no differences in the rate of nuclear maturation after 24 h of culture. After 44 h, 77% of COCs incubated in the absence of CIL were at metaphase II (MII) compared to 35-45% MII when cultured in the presence of 1, 5, 10, or 20 μM CIL (P < 0.001). Furthermore, CIL supplementation resulted in approximately half the COCs arresting at germinal vesicle stage (GV) after 44 h of culture. While there were no significant differences in the MII rates of COCs cultured in 0, 0.01, and 0.1 μM CIL, significantly more COCs were at metaphase I (MI) at 44 h compared to control COCs (0 μM CIL, P < 0.05). The time course experiment (Exp 2) demonstrated that nuclear maturation was delayed by 12 h with 0.1 μM CIL, compared to the absence of CIL, with comparable MII rates being achieved at 56 h for 0.1 μM CIL (72%) and 44 h for controls (0 μM CIL = 73%).

These results demonstrate that porcine oocyte maturation can be induced in vitro by FSH in the presence of a low dose of type 3 PDE inhibitor resulting in a delay in the resumption and completion of nuclear maturation. Further investigations are underway to determine if CIL treatment prolongs gap junction communication and improves the developmental competence of porcine oocytes.

   
    
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2015