Endocrine Abstracts

Little is know about the effects of IGFs on the early preantral stages of follicle development. The aim of this study was to investigate the effects of IGF-I on recruitment and survival of human preantral follicles in vitro. Small ovarian cortical biopsies were obtained at laparoscopy, with informed consent and local ethical committee approval, from 27 premenopausal women. The tissue was divided and randomly allocated to 5 conditions. The first piece was fixed immediately as a...

Cytochrome P450arom (aromatase), a marker of granulosa cell differentiation, and CTGF mRNA expression are inversely related in the developing rat follicle, but the cause/effect nature of the relationship is not known. Here, we used semi-quantitative in situ hybridization to analyze the expression of these genes during follicular development in the rat. The effect of CTGF on aromatase enzyme activity in isolated granulosa cells was determined by conversion of ...

The prokineticins (PK1 and PK2, also known as endocrine gland vascular endothelial growth factor [EG-VEGF] and Bv8 respectively), which bind to two closely homologous G-protein coupled receptors, PKR1 and PKR2, have been identified as novel angiogenic factors in endocrine tissue. However, little information is available on their expression and distribution in the uterus. The objectives of this study were to examine the expression and localisation of prokineticins and their rec...

Prostaglandin (PG) E2 has been implicated in benign and neoplastic endometrial pathologies. PGE2 exerts its function by coupling to 4 subtypes of G protein coupled receptors (EP1-EP4). Recently a role for the EP2 receptor in angiogenesis has been established. This study investigated signal transduction and vascular endothelial growth factor (VEGF) expression by the EP2 receptor in Ishikawa endometrial epithelial cells. Ishikawa cells were stably transfect...

Parturition in the ewe is initiated by the fetus following the cortisol rise via activation of the hypothalamic-pituitary-adrenal axis and increased intrauterine PG production. Dietary n-6 PUFAs, noteceably linoleic acid (LA) are the precursors for PG synthesis. The maternal intercotyledonary endometrium is the main site of PGF2alpha during labour. This study investigated the effect of dietary n-6 PUFA supplementation on uterine PG production at term. Ewes (n=32) we...

PCOS is associated with increased biochemical risk markers for cardiovascular disease, particularly low HDL cholesterol and increased triglycerides. There is accelerated progression to type 2 diabetes and hypertension in middle age. These biochemical abnormalities associate with insulin resistance which is present to a greater extent than can be explained by obesity alone. Notwithstanding, hard endpoint data in terms of increased cardiovascular mortality remains elusive. Infla...

Insulin resistance and hyperinsulinaemia are well-recognised characteristics of anovulatory women with polycystic ovary syndrome (PCOS) but, paradoxically, steroidogenesis by PCOS granulosa cells remains responsive to insulin. The hypothesis to be tested in this study was that insulin resistance in the ovary is pathway-specific i.e. is confined to the metabolic effects of insulin (i.e. glucose uptake and metabolism) whereas its steroidogenic action remains intact. Granulosa-lu...

Orexins (A & B) are derived from a common 130 amino acid precursor peptide, prepro-orexin, by proteolytic cleavage, and orchestrate their actions by binding and activating two types of G-protein coupled receptors, orexin-1 receptor (OX1R) and orexin-2 receptor (OX2R). The OX1R preferentially binds orexin-A, whilst OX2R binds both orexin-A and ?B, with similar affinity. Besides playing a role in the regulation of feeding and energy homeostasis, orexins appear to increase se...