We have developed an assay that can detect relative changes in the amount of a non-cAMP inhibitor of maturation present in cumulus cells (Eppig et al., 1983, Dev. Biol., 100:39-49). Using this assay in which accelerated maturation of a group of treated cumulus cell-oocyte complexes relative to untreated complexes indicates a decrease in the amount of inhibitor, results of the experiments descri...

This paper postulates that in the ovary, the close association between the cumulus cells and the oocytes permits the fertilizing ability of the oocytes to be determined indirectly through cumulus cell DNA status. The objective was to use a modified comet assay to analyse cumulus cell DNA and relate the data to oocyte fertilization after intracytoplasmic sperm injection (ICSI) procedures. Oocyte...

Cumulus expansion and oocyte maturation are central processes in ovulation. Knowledge gained from rodent and other mammalian models has revealed some of the molecular pathways associated with these processes. However, the equivalent pathways in humans have not been thoroughly studied and remain unidentified. Compact cumulus cells (CCs) from germinal vesicle cumulus oocyte complexes (COCs) were ...

background: linoleic acid (la) is a polyunsaturated fatty acid present in high concentrations in follicular fluid, when added to maturation culture media, it affects oocyte competence.objective: in the present study, we investigated effect of linoleic acid supplementation on in vitro maturation, embryo development and apoptotic related gene expression in ovinematerials and methods: the experime...

In ovarian antral follicles cumulus cells (approximately 1,000/follicle) closely surround the oocyte, and mural granulosa cells (approximately 50,000/follicle) are distributed at the periphery. Previous work (Salustri, A., Yanagishita, M., and Hascall, V. C. (1990) Dev. Biol. 138, 26-32) showed that oocytes produce a factor(s) which stimulates hyaluronic acid (HA) synthesis by cumulus cells dur...

A typical mammalian egg is surrounded by an outer layer of about 3,000 cumulus cells embedded in an extracellular matrix rich in hyaluronic acid. A current, widely proposed model is that the fertilizing sperm, while it is acrosome intact, passes through the cumulus cell layer and binds to the egg zona pellucida. This current model lacks a well-supported explanation for how sperm penetrate the c...

BACKGROUND Oocytes are the female gametes which establish the program of life after fertilization. Interactions between oocyte and the surrounding cumulus cells at germinal vesicle (GV) stage are considered essential for proper maturation or 'programming' of oocytes, which is crucial for normal fertilization and embryonic development. However, despite its importance, little is known about the m...

OBJECTIVE To determine whether the incidence of apoptosis in mature oocyte cumulus cells changes after insemination related to infertility. DESIGN Prospective study. SETTING Public hospital and university. PATIENT(S) One hundred women undergoing in vitro fertilization and embryo transfer (IVF-ET). INTERVENTION(S) Collection of cumulus cells from IVF-ET cycles with different infertility ...

Background: Oocyte in vitro maturation success rate is still low in compareision to oocyte in vivo maturation. Thus prediction and improvement of oocyte competency are two critical issues in assisted reproductive technology. New insights into oocyte-cumulus cell regulatory loop may assist our optimization of in vitro maturation technique. Maturation and developmental competency of cumulus oocyt...