background: this study was aimed to assess the effects of angiotensin ii (ang ii) supplementation to the in vitro maturation (ivm) and in vitro culture (ivc) media of vitrified-warmed ovine oocytes on their developmental competence and expression of na+/k+/atpase in resulting embryos. methods: the slaughterhouse-derived immature oocytes (n=1069) were randomly distributed into four experimental ...

In canine species, in vitro maturation (IVM) rates of oocytes collected from anoestrous ovaries are low (<20%). Several IVM media have been tested without significant improvements. A critical step in the evaluation of culture conditions is the observation of the meiotic stage reached by the oocytes. The present study was designed to investigate the chromatin patterns of in vitro matured oocytes...

A major side-effect of controlled ovarian stimulation (COS) in patients with polycystic ovarian syndrome (PCOS) is the risk of ovarian hyperstimulation syndrome (OHSS). In-vitro maturation (IVM) of immature oocytes represents a potential alternative for the fertility treatment of these patients. Two patients at high risk of OHSS were primed with 10,000 IU HCG 36 h before oocyte retrieval. After...

The slaughtered cows or heifers have a large number of immature oocytes within primordial follicles or developing follicles. Therefore, it is useful to aspirate immature oocytes, which would be wasted if left unprocessed, from ovaries; subsequently they are matured in vitro (IVM), fertilized in vitro (IVF), and cultured in vitro (IVC). Also most recently it has been shown that immature oocytes ...

Cryopreservation of embryos, oocytes, or ovarian tissues is the main option for female fertility preservation. Oocyte cryopreservation has emerged as especially important: the dramatic increase in the number of infants born from vitrified oocytes indicates that it is becoming one of the most important intervention options. However, oocyte cryopreservation with standard controlled ovarian hypers...

The aim of this study was to evaluate the effect of ethylene glycol (EG) concentration, equilibration time, and the use of two disaccharides in the vitrification solution used on immature bovine oocytes that were thawed and then matured in vitro. Factorial combinations of the following were tested: three equilibration solutions (ES), containing 3, 20 or 40% EG; three equilibration times, 0.5, 5...

OBJECTIVE We found previously that interferon regulatory factor (Irf)-1 is a germinal vesicle (GV)-selective gene that highly expressed in GV as compared to metaphase II oocytes. To our knowledge, the function of Irf-1 in oocytes has yet to be examined. The present study was conducted to determine the relationship between retinoic acid (RA) and RA-mediated expression of Irf-1 and the mouse oocy...

BACKGROUND Relaxin is a small peptide also known as pregnancy hormone in many mammals. It is synthesized by both male and female tissues, and its secretions are found in various body fluids such as plasma serum, ovarian follicular fluid, utero-oviduct secretions, and seminal plasma of many mammals, including pigs. However, the presence and effects of relaxin in porcine gametes and embryos are s...

BACKGROUND Zona pellucida binding assays (ZBAs) have proven useful in determining the fertilising ability of spermatozoa in several species. Most ZBAs use fresh or salt-stored oocytes collected from fresh ovaries but because ovaries are not easy to obtain on a regular basis, chilled and frozen-thawed ovaries have been tested, with varying results. The present study tested the hypothesis that ca...

BACKGROUND Approximately 20% of oocytes are classified as immature and discarded following intracytoplasmic sperm injection (ICSI) procedures. These oocytes are obtained from gonadotropin-stimulated patients, and are routinely removed from the cumulus cells which normally would mature the oocytes. Given the ready access to these human oocytes, they represent a potential resource for both clinic...