Endocrine Abstracts

While secretion of GnRH pulses from hypothalamic neurones every 1 to 4 h is the normal mode of release in adult males and females, resulting in pulsatile LH secretion from pituitary gonadotropes, only in females does the pattern of GnRH secretion change from pulsatile to a surge mode in response to estradiol to generate the preovulatory LH surge. We have investigated the changes in gonadotropes which ensure that they are responsive to the GnRH surge allowing the release of suf...

Alan McNeilly, MRC Human Reproduction Sciences Unit, Edinburgh, UK AbstractAfter graduating from Nottingham (BSc) and Reading (PhD) Universities with degrees in animal physiology, Dr McNeilly joined Tim Chard at Barts for 4 years developing gonadotrophin and prolactin assays for clinical application. During those 4 years he gained experience in clinical endocrinology. Collaborations with Roger Short and David Baird led...

In these times of restricted funding, it becomes crucially important that you position yourself to be the only possible candidate for future employment in a postdoctoral position or any other career path that you chose. The time to do this is during your PhD and MD studies and during your first postdoc. There are no hard and fast rules about how you do this, but some pointers may help. First, you must have a passion for research if this is what you want to do. If this is a job...

When you sit in meetings I know you will all have thought at different times that this is the most (tick one of the following boxes) – boring – incomprehensible – ridiculous – interesting – inspirational – fantastic – talk you have ever heard. Now that oral presentations at meetings are rare for many with posters taking centre stage it is really important to make the best of the opportunity to impress potential future employers etc with your ...

Conservation is a tricky subject to discuss when people actually are asked to consider the present situation, and the virtual world that many live in today. Many of the losses of species are due to human intervention, through killing for pleasure, food, or profit (greed), or through habitat destruction. The species are innocent. Zoos provide a sanctuary for maintaining some numbers of species on a limited scale, but can only ever be a stop-gap to maintain the species, although...

Birth of a single baby gives that infant the best possible start to life. In mono-ovular species like man there is a tight control over the hypothalamic–pituitary–ovarian axis to try to ensure that there is also sufficient time between births to allow the infant to develop to its full potential. Breastfeeding suppresses fertility by modulating pulsatile LH but not FSH secretion delaying the final stages of ovarian follicle maturation and the return of fertility in br...

Alterations in the rate of glucocorticoid(GC) metabolism induce compensatory changes in GC secretion under the control of the hypothalamic-pituitary-adrenal (HPA) axis. The principal routes of metabolic clearance of GCs are by hepatic A-ring reduction however the regulation of these enzymes is poorly understood. Recently we and others have demonstrated that bile acids act as potent inhibitors of GC metabolism by 5beta-reductase and 11beta-hydroxysteroid dehydrogenases in vi...

Diet induced obesity is associated with an increased relative risk of developing type 2 diabetes, hypertension, dyslipidemia and cardiovascular complications. In addition to these co-morbidity factors there is increasing evidence to suggest that obese insulin resistant individuals show impaired negative feedback control of the HPA axis in response to stress. Here we investigate HPA axis response to an acute stress following high fat feeding in rats.Male ...

Hepatic A-ring reduction of glucocorticoids is enhanced in obesity, perhaps contributing to compensatory activation of the hypothalamic-pituitary-adrenal axis and adrenal androgen excess. One pathway activated is the formation of tetrahydro metabolites by two sequential steps catalysed by 5beta-reductase (5bR) followed by 3alpha-hydroxysteroid dehydrogenases (3HSD). However, regulation of these enzymes is understood poorly. 5bR and 3HSD are also involved in the conversion of c...

Cytotoxic chemotherapy is a well recognised cause of premature ovarian failure (POF). A proportion of women with biochemical evidence of POF following treatment recover ovarian function with a return of normal menses and fertility, but there are no indicators that allow the identification of this subgroup of patients. In addition, we have previously reported only minor reductions in BMD in a cohort of women with POF following cytotoxic chemotherapy and had postulated that this...