background: effect of different doses of cysteamine on rate of in vitro maturation (ivm ) , in vitro fertilization (ivf ) and glutathione (gsh ) level was studied. metaphase ii (mii) spindle area was analyzed for quantification of shape and size of oocytes.   methods: female mice were primed with 5 iu of pregnant mare’s stimulating gonadotrophin . germinal vesicle (gv ) oocytes were retrieved 4...

We studied the role of the Na+/Ca2+ exchanger (NCX) in modulating oocyte postovulatory aging by observing changes in NCX contents and activities in aging mouse and rat oocytes. Whereas the NCX activity was measured by observing oocyte activation following culture with NCX inhibitor or activator, the NCX contents were determined by immunohistochemical quantification. Although NCX was active in f...

objective: retinoids are recognized as important regulators of cell differention and tissue function. previous studies, performed both in vivo and in vitro, indicate that retinoids influence several reproductive events. in this study, we investigated the effect of all-trans retinoic acid (t-ra) on maturation and fertilization rate of immature oocytes (germinal vesicle). materials and methods: g...

Fertilization of the immature, prophase I-arrested mouse oocyte produces multiple Ca2+ transients similar to those of the mature, metaphase II egg; however, the first Ca2+ transient is much lower in amplitude and shorter in duration. In contrast to prophase I-arrested oocytes, maturing oocytes fertilized after germinal vesicle breakdown have first Ca2+ transients similar to those of mature fert...

Background: In mammalian ovaries, loss of over two-thirds of germ cells happens due to cell death. Nonetheless, the exact mechanism of cell death has yet to be determined. The present basic practical study was designed to detect 3 types of programmed cell death, namely apoptosis, autophagy, and necrosis, in murine embryonic gonadal ridges and neonatal ovaries.Methods: Twenty gonadal ridges and ...

Background: Gamete cryopreservation is an inseparable part of assisted reproductive technology, and vitrification is an effective approach to the cryopreservation of oocytes. The aim of this study was to investigate vitrification effects on the expression levels of mitochondrial transcription factor A (Tfam) and mitochondrial-encoded cytochrome c oxidase subunit 1 (Cox1) in mouse metaphase II o...

Female meiosis is a fundamental area of study in reproductive medicine, and the mouse oocyte model of in vitro maturation (IVM) is most widely used to study female meiosis. To investigate the probable role(s) of an unknown protein in female meiosis, the method traditionally used involves microinjecting a specific antibody into mouse oocytes. Recently, in studies on somatic cells, peptide nanopa...

background: caffeine increases the camp production that stimulates spermatozoa movement. caffeine is also used for induction of in vitro acrosome reaction in mammalian spermatozoa, an important step in achieving fertilization. objective: the aim of this study was to assess the effect of caffeine on sperm's motility, vitality and laboratory fertilization rates in mouse in two t6 and m16 media. m...

Background: The aim of this study was to compare two vitrification systems (Cryotop and OPS) on mouse MII oocytes and evaluate its effects on expression of heat shock protein A1A and MnSOD genes. Materials and Methods: Groups of about 15 oocytes without cumulus complexes (granulose, et. al.) were collected and exposed to equilibration and vitrification solutions before loading the oocytes into ...

BACKGROUND There is an increased incidence of rare imprinting disorders associated with assisted reproduction technologies (ARTs). The sex-specific epigenetic modifications that are imposed during gametogenesis act as a primary imprint to distinguish maternal and paternal alleles. The most likely candidate for the gametic mark is DNA methylation. However, the timing of DNA methylation acquisiti...