Endocrine Abstracts

Receptor-mediated endocytosis (RME), involving megalin and cubilin, mediates renal proximal-tubular reabsorption of glucose, proteins and hormones including insulin, parathyroid-hormone and vitamin D. RME disruption occurs in Dent’s disease patients with mutations of the chloride/proton antiporter, CLC-5, who suffer from low-molecular-weight proteinuria, hypercalciuria, nephrolithiasis and renal failure. To further investigate the RME role of CLC-5 we established conditio...

Background: Minimally invasive parathyroidectomy (MIP) is usually performed with the concurrent use of intraoperative adjuncts for good outcome.Objective: We wanted to show that a good success rate can be achieved in MIP without routine use of any intraoperative adjuncts.Methods: A prospective case series of the first 100 patients who underwent MIP for primary hyperparathyroidism by a single surgeon at a single institution were inc...

Calcium mobilization from intracellular stores represents an important cell signalling process that is regulated, in mammalian cells, by inositol-1,4,5-triphosphate (IP3), cyclic ADP ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP). Intracellular calcium is important for mobilization of secretory granules to the plasma membrane in preparation for exocytosis. NAADP mobilizes calcium from lysosome-related acidic compartments and it has recently...

Recent studies have demonstrated that rather than being a collection of heterogeneously dispersed cells, the pituitary gland is wired by multiple and specific endocrine cell networks to synchronise hormone release. Prolactin (PRL) is primarily important for lactation. In response to changing physiological demands during pregnancy and lactation the pituitary has the ability to expand and contract its cell number. We have investigated changes in lactotroph morphology and cell-to...

Two growth hormone releasing hormone-like peptides (GHRH-LP-1 and GHRH-LP-2) are expressed in chickens. Although GHRH-LP-1 displaces the binding of labelled human GHRH to chicken pituitary membranes and stimulates the accumulation of cAMP in HEK 293 cells transfected with the chicken (c) GHRH receptor it has <1% of the potency of human GHRH1–32 and has little, if any, growth hormone (GH) - releasing activity in chickens. GHRH-LP-1 is thus unlikely to be the...

Background: Insulin resistance and obesity are characteristic features of PCOS. Oxidative stress leads to the formation of lipid peroxidation products in the skeletal muscles and has the potential to interfere with insulin signaling and thereby contribute to insulin resistance. Malondialdehyde (MDA) is a lipid peroxidation end product and is widely used as a marker of oxidative stress.Rimonabant has been shown to reduce weight and insulin resistance in o...

Mammalian pituitary gland development is well established on a molecular and morphological level. In developmental biology the use of chick and zebrafish models is common but despite chicken pituitary gland development being characterised in 1952 these models have only recently been regularly employed in pituitary studies. The third member of the natriuretic peptide family, C-type natriuretic peptide (CNP), has been investigated in rodent embryos but little is known about its ...

Introduction: Polycystic ovary syndrome (PCOS) is associated with known cardiovascular risk factors, consequently predisposing to premature cardiovascular disease. Blood clot structure has been shown to predict predisposition to atherothrombosis and the aim of this study was to investigate the effects of rimonabant and metformin on clot structure/function in women with PCOS.Methods: Twenty women with PCOS were recruited in a randomised open labelled para...

Introduction: Lack of radioiodine uptake in differentiated thyroid carcinoma (DTC) is a big diagnostic and therapeutic problem. This sign is associated with worse prognosis. In NRADTC patients with elevated thyreoglobulin levels with no evidence of disease in radioiodine scintigraphy, scintigraphy with the somatostatin analog labeled with 99mTc seems to be an alternative imaging method.Aim: Assessment of scintigraphy with the somatostatin anal...

All metabolites in the body are in a state of constant flux, and changes in their levels may reflect either increased rate of production or decreased clearance, or both. Stable isotope technology can be used in physiological studies to determine mechanisms mediating changes in metabolites. For example, the decline in blood glucose following administration of insulin could be due to either increased uptake into peripheral tissues, or (as is the case) by suppression of hepatic g...