Endocrine Abstracts

In the adult animal the Leydig cells are the primary source of androgens in the male and are required to maintain fertility and male behaviour. To help towards understanding the development, control and function of these cells we have analysed the adult Leydig cell transcriptome using the SAGE technique which provides a comprehensive and quantitative gene expression profile of cells or tissues. Leydig cells were isolated from normal adult mouse testes using collagenase and the...

1,25-hydroxyvitamin D3 receptors (VDR) are present on rat granulosa cells and on human ovarian cancer cells, however little is known about 1,25-hydroxyvitamin D3 (1,25-(OH)2D3) function in the ovary. Vitamin D deficient rats have reduced fertility, and VDR null mutant mice demonstrate impaired folliculogenesis. Vitamin D metabolites have been detected in follicular fluid. The aim of this study was to investigate the effect of a range of conce...

Polycystic ovary syndrome (PCOS) is the commonest cause of anovulatory infertility in women, but its aetiology is poorly understood. There is evidence for a primary disorder of androgen secretion, which has its origins before puberty, but it is not clear how this may cause the characteristic ovarian abnormalities. We have developed an ovine model for PCOS to explore possible differences between the small preantral follicles of androgenised female lambs with those of normal ova...

Heterotrimeric G proteins mediate signalling from 7 transmembrane domain receptors to a variety of intracellular effectors. Regulators of G protein signalling (RGS) are a novel family of proteins, that act as GTPase activating proteins. In the human myometrium signalling via G proteins may be altered during pregnancy and labour, suggesting a physiological role of G proteins in human gestation. Our aim was to investigate the expression of RGS proteins in the human myometrium. E...

Reproductive activity of male Rhabdomys pumilio is inhibited by exposure to a combination of reduced ambient temperature and food availability. However, the extent of this inhibition is reduced in mice that have maintained a body fat reserve. To determine if body fat stimulates reproduction via leptin, we treated 5 non-scrotal mice with exogenous leptin (40 micrograms subcutaneously twice per day for four days). A further 5 mice served as untreated controls. To determin...

Introduction: In sheep, modest maternal nutrient restriction over the period of rapid placental growth restricts placentome growth. Maternal plasma IGF-I concentration is unaffected but effects on placental IGF-I receptor mRNA expression are not known.Methods: Twenty singleton-bearing ewes of similar body weight and parity were entered into the study. Ten ewes consumed 60% of their total energy requirements (i.e. nutrient restricted, NR) from 28 to 80 da...

Prostaglandins are strongly implicated in the onset and maintenance of human parturition and their synthesis is increased within the uterus in association with labour. Enzymes involved in their synthesis, (cyclo-oxygenase-2), and catabolism, (prostaglandin dehydrogenase) are up and down-regulated respectively, in association with labour. The human prostaglandin dehydrogenase (PGDH) gene is approximately 34kb in size. A large 5' promoter region containing numerous potential tra...

Objectives: To evaluate changes in gonadotrophins, total (TT) and free (FT) testosterone, SHBG, insulin and c-peptide levels during weight lost after bariatric surgery.Material and methods: Seven (n=7) patients submitted to bariatric surgery for treatment of severe obesity were followed-up over time. Before surgery mean age was 32,857 (19-56) years old, mean weight was 170,571 kg (± 37,362) and mean BMI was 58,824 kg per m2(± 14,...

Gonadotrophins such as luteinizing hormone (LH) and human chorionic gonadotrophin (hCG) exert their actions on progesterone (P4) synthesis, at least in part, by regulating luteal cell phosphorylation via ser/thr kinases particularly cAMP-dependent protein kinase (PKA). Hence the aim of this study was to identify changes in P4 secretion and PKA expression during luteinization of human granulosa cells (GCs) in vitro. GCs, obtained from follicular asp...