Endocrine Abstracts

ObjectiveTo report and discuss a kindred with pathological hyperprolactinaemia.Case 1 (Proband)A 39-year old man presented in June 2003 with 3-years of erectile dysfunction (ED) and was found to have hyperprolactinaemic hypogonadotrophic hypogonadism: LH 1.0 & FSH 1.5 U/L, Testosterone 5.8 nmol/L, PRL 4154 mU/L. Pituitary function was otherwise normal. MRI demonstrated an intrasellar macroadenoma. Cabergo...

A 30 year old gentleman presented with long standing symptoms of polyuria and polydypsia and poor libido. On examination he was short (155 cm), weighed 108 kg with a body mass index of 45.1. Investigations revealed normal Blood Glucose, renal function, liver function and calcium. Water deprivation test confirmed the diagnosis of Cranial Diabetes Insipidus. He was started on DDAVP tablets 100 microgram’s twice daily. Further tests showed a normal IGF-1, synacthen test and ...

Insulin-stimulated lactate production by granulosa cells (GC) appears to be compromised in polycystic ovary syndrome (PCOS), and this may have an adverse effect on the provision of 3-C units essential for oocyte development. The insulin-sensitiser, metformin, has been used successfully as an adjunct to gonadotrophin therapy in PCOS. Our objective was to establish whether metformin increased AMP kinase (AMPK) activity and lactate production in human GC.GC...

In target tissues, CNP acts via the cell surface guanylyl cyclase B (GC-B) receptor to stimulate cGMP accumulation. Transgenic mice studies deleting either CNP or the GC-B receptor suggest a role for CNP in regulating bone formation and pituitary growth hormone secretion. Our previous studies have implicated a role for CNP in inhibiting calcium transients in alphaT3-1 pituitary gonadotroph cells; however the biological consequence of cGMP accumulation remains unclear. Therefor...

IntroductionTrue resistance to cabergoline in patients with hyperprolactinaemia has only rarely been reported. We describe a patient with macroprolactinoma who initially responded to cabergoline, but then developed a progressive increase in PRL levels.Clinical caseA 78-year-old male presenting with headache and left temporal hemianopia was found to have a macroprolactinoma with suprasellar/cavernous sinus ext...

Glucocorticoids (Gcs) are important regulators of cellular homeostasis, with their effects mediated by the intracellular glucocorticoid receptor (GR). Once activated, the GR may initiate rapid effects within the cytoplasm, but also translocate to the nucleus to affect gene transcription. The subcellular localisation of the GR is therefore an important determinant in the cellular response to Gcs.To analyse subcellular trafficking of the GR, HeLa cells wer...

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...

C-type natriuretic peptide (CNP) acts via its specific membrane-bound guanylyl cyclase receptor, GC-B, to stimulate cGMP production. Stimulation of cGMP impinges upon PKG and PKA signalling, leading to cell proliferation and cell cycle events. In endothelial cells, CNP is thought to perform a predominantly anti-mitogenic role, but the role of CNP on cell proliferation, cell cycle and DNA synthesis in pituitary cell lines has yet to be established. Using the mouse gonadotroph-d...