Endocrine Abstracts

Introduction: It is recognised that osteocytes, by secreting sclerostin plays a more central role in bone homeostasis. Sclerostin is a physiological inhibitor of bone formation. By binding to the LRP5/6 receptor sclerostin inhibits the Wnt signalling pathway. A cross-sectional study was undertaken to ascertain whether an endogenous sclerostin circadian rhythm exists in healthy individuals.Subjects and methods: Six healthy young men with normal BMD were a...

Introduction: Osteotropic hormones demonstrate circadian rhythms which are integral to bone homeostasis. Sclerostin is a physiological inhibitor of bone formation. We have established that Sclerostin has a distinct circadian rhythm with a nocturnal peak. Analysis was performed to determine the relationship of Sclerostin levels to PTH, Calcium, Phosphate, βCTX and P1NP in healthy young men.Methods: Six healthy young men with normal BMD were admitted ...

Introduction: There is controversy over which form of biochemical testing is best for screening for phaeochromocytoma/paraganglioma (PHAEO/PGL). Measurement of plasma metanephrines is the most sensitive test but is less specific and lacks widespread availability, and so many centres opt to measure 24-h urinary excretion of catecholamines and metanephrines. However, the standard 24-h urinary catecholamine profile also includes dopamine (DA), vanillylmandelic acid (VMA) and homo...

The final reaction for cortisol production in the adrenal gland is catalysed by the 11β-hydroxylase enzyme, encoded by the CYP11B1 gene. Variants in this gene have been associated with alterations in cortisol levels, which increase blood pressure. This gene is traditionally thought to consist of 9 exons. However, recent evidence has predicted the existence of at least one alternatively spliced form.The presence of novel CYP11B1 mRN...

Background: Testosterone deficiency is common in obesity and in type 2 diabetes mellitus. It is hypothesised that the expanded adipose pool, which is the major source of aromatase in men, depletes testosterone levels by excess conversion to estradiol. Individuals with either the GG rs2470152 polymorphism in intron 1 or a high number of TTTA repeats in intron 4 of CYP19 are known to have greater aromatase activity with demonstrable effects upon plasma estradiol and osteoporosis...

Introduction: Two identically designed randomized, placebo-controlled double-blind studies (one conducted in North America and the other one in Europe and Australia) showed that an oral contraceptive containing estradiol valerate (E2V)/dienogest (DNG) in an estrogen step-down, progestogen step-up 28-day regimen was effective in women with heavy and/or prolonged menstrual bleeding without organic pathology. Both studies applied a strict definition of treatment succes...

Background: Hyponatraemia is the commonest electrolyte abnormality in clinical practice, and may be a biochemical manifestation of different diseases including malignancy. About 14% of hyponatremia in medical inpatients is due to underlying tumour related conditions.We present a case of 68 years widow who was referred by her General Practioner with 3 weeks history of nausea, occasional vomiting, confusion, increased urinary frequency, and urinary inconti...

Background: Hyponatraemia is the commonest electrolyte abnormality in clinical practice, and may be a biochemical manifestation of different diseases including malignancy. Uterine neuroendocrine tumours causing hyponatraemia are rare and can cause a diagnostic challenge.We present a case of 68 years widow who presented with 3 weeks history of nausea, occasional vomiting, confusion, increased urinary frequency, urinary incontinence, chronic constipation, ...

Aim: In chronic kidney disease (CKD) elevated aldosterone (Aldo) levels are a poor prognostic indicator, particularly in the context of a high dietary sodium intake, through unclear mechanisms. Blockade of the mineralocorticoid receptor (MR) improves surrogate patient outcomes. We hypothesised that regulation of aldosterone biosynthesis is disordered in CKD and aimed to compare this in a cohort of patients with CKD with subjects with essential hypertension (EH).<p class="a...

Circulating estrogens decrease after the menopause from 60–400 to 5–30 pg/ml in postmenopausal women and in men are below 30 pg/ml. These low physiological concentrations present an analytical challenge. Analysis of steroids by tandem mass spectrometry is attractive due to its high specificity compared with immunoassays. However, estrogens do not ionise efficiently and therefore chemical modifications are necessary to achieve the sensitivity required.<p class="ab...