Searchable abstracts of presentations at key conferences in endocrinology

ea0011p687 | Reproduction | ECE2006

Anti-Mullerian hormone (AMH) production by and amh type-II receptor (AMHRII) in normal human ovaries

Hanna L , Pellatt L , Rice S , Whitehead S , Mason H

AMH, the fetal testicular sexual differentiative factor, is now implicated in adult ovarian function. Antral follicle immunohistochemistry demonstrated AMH protein and message, the staining peaking around 4 mm. Interestingly, AMH-knockout mice have increased FSH sensitivity. Our aim was to measure AMH in follicular fluid and cell-conditioned medium and AMHRII in normal ovaries from women undergoing TAH/BSO.Follicles were dissected intact, follicular flui...

ea0008p82 | Steroids | SFE2004


Rice S , Whitehead SA

Phytoestrogens bind weakly to oestrogen receptors and can initiate oestrogen-dependent transcription. They are promoted as natural alternatives to HRT and yet epidemiological evidence suggests that they may protect against breast and prostate cancer. Studies in cell-free preparations have shown that phytoestrogens can inhibit the activity of aromatase and that the inhibition is, at least partly, competitive with androgen substrates. The question as to whether chronic exposure ...

ea0003p220 | Reproduction | BES2002

Phytoestrogens as inhibitors of aromatase and 17beta-hydroxysteroid dehydrogenase type 1 in luteinized human granulosa cells

Lacey M , Whitehead S

Studies on breast cancer cell lines, placental microsomes and purified recombinant enzymes have shown that various phytoestrogens can inhibit both aromatase and 17beta-hydroxysteroid dehydrogenase (HSD) enzymes. This has led to the suggestion that certain phytoestrogens may exert their endocrine disrupting functions by enzyme inhibition rather than their ability to bind weakly to oestrogen receptors. Previous studies have shown that genistein, the active ingredient of soy, ind...

ea0002oc29 | Reproduction | SFE2001

Evidence for FSH induction of 17beta-hydroxysteroid dehydrogenase type 1 in luteinized human granulosa cells

Lacey M , Whitehead S

Numerous investigations have shown that FSH can induce aromatase in granulosa cells obtained from natural ovarian cycles. In contrast granulosa luteal (GL) cells obtained from patients undergoing procedures for IVF are generally insensitive to FSH-induction of aromatase. A few studies, however, have reported that GL cells can be sensitized to this gonadotrophin. In these experiments we compared the conversion of various steroid substrates - namely pregnenolone and androstenedi...

ea0011p712 | Reproduction | ECE2006

Stage-specific mRNA expression of androgen receptor correlated with FSH receptor in individual pre-antral follicles isolated from human ovary

Rice S , Ojha K , Whitehead S , Mason H

Recent evidence indicates that the increase in follicle numbers seen in PCOS occurs early in folliculogenesis, and that androgens are implicated in this. In primates and sheep, androgen excess in-utero results in ovarian changes similar to those in PCOS. We have recently shown using a novel in ovo model, that testosterone added to implanted human tissue increased primary follicles compared to untreated tissue (Qureshi et al. 2005). This is similar to the p...

ea0008p78 | Reproduction | SFE2004

Androgens inhibit atresia and retard early development of ovarian follicles: a model for PCOS?

Qureshi AI , Bano G , Whitehead S , Nussey SS , Mason HD

BackgroundPCOS is the commonest endocrinopathy in women. PCO are typified by increased ovarian follicles. The aetiology is unknown, but may be due either to enhanced follicular growth, reduced atresia, or both. Hyperandrogenism is almost universal either clinically or biochemically and in primates and sheep androgen excess in-utero produces ovaries phenotypically identical to those in PCOS. There have been no analyses of the effects of androgens on early...

ea0007p181 | Reproduction | BES2004

The CAM technique and follicle development

Qureshi A , Bano G , Whitehead S , Nussey S , Mason H

BackgroundCurrent techniques to study the early stages of follicular development (i)in vitro(/i) are handicapped by the spontaneous wholesale transition of primordial to primary follicles and by primary follicle arrest. We have circumvented this problem by culturing fragments of ovarian cortical tissue on the chorioallantoic membrane (CAM) of chick embryos and shown it to be successful for the (i)in ovo(/i) culture of cortical slices from a variety of sp...

ea0006p57 | Reproduction | SFE2003

Ovarian follicle culture: an old technique revisited

Qureshi A , Bano G , Whitehead S , Nussey S , Mason H

Current techniques to study (i)in vitro(/i) the early stages of follicular development are handicapped by the spontaneous wholesale transition of primordial to primary follicles. Implantation of ovarian tissue into SCID mice is possible but expensive. We have, therefore, adapted a model first described in 1958. Fragments of ovarian cortex are implanted on the chorioallantoic membrane (CAM) of 5-6 day old fertilised chick eggs. The membrane is rich in blood vessels and results ...

ea0003p103 | Diabetes & Metabolism | BES2002

The utility of the HOMA model for identifying women with polycystic ovarian syndrome (PCOS) who are insulin resistant

Heald A , Whitehead S , Anderson S , Laing I , Buckler H

OBJECTIVE Recent studies have shown the benefits of insulin sensitising agents such as Metformin in the treatment of infertility and hirsuitism in PCOS. However not all women with PCOS are insulin resistant. Within a clinic population of women referred for treatment of hirsuitism, we examined the utility of fasting insulin/glucose measurement in identifying which women were insulin resistant.DESIGN We evaluated an outpatient clinic group of 25 PCOS pati...

ea0012oc23 | Pituitary, ovary and steroids | SFE2006

Metformin inhibits ovarian aromatase and anti-Müllerian hormone (AMH) production

Rice S , Pellatt L , Feldman D , Malloy P , Whitehead S , Mason H

Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility. Although the cause of the anovulation is unknown there are a number of endocrine candidates; hyperinsulinaemia, raised steroid production and increased levels of the sexual differentiative factor anti-Müllerian hormone (AMH). The latter is increasingly thought to be an inhibitor of folliculogenesis. Hyperinsulinaemia in PCOS is now widely treated with metformin and we have shown that thi...