Endocrine Abstracts

We describe a 3 year old Scottish girl with polyuria and nocturia and a past history of congenital heart disease. In addition to her excess fluid intake she had reduced food intake, failure to thrive and growth failure. Her sister, father, grandfather and a paternal aunt and uncle had a clear history of polyuria, nocturia and excess thirst. A fluid deprivation test revealed peak serum Na, serum and urine osmolalities were 147 mmol/L, 300 mOs/kg, 176 mOs/kg, respectively, in th...

The key enzymes in the terminal stages of human adrenal gland corticosteroid biosynthesis are aldosterone synthase (AS) and 11-beta hydroxylase (11beta-OHase). Their amino acid sequences differ by only 7% but they exhibit markedly different enzymatic activities. AS is expressed solely in the zona glomerulosa and converts 11-deoxycorticosterone (DOC) to aldosterone whereas 11beta-OHase is expressed mainly in the zona fasciculata and produces cortisol from 11-deoxycortisol. The ...

Background: The aldosterone to renin ratio (ARR) is a useful screening test for primary aldosteronism. Renin can be measured as activity or concentration; the accuracy of the ARR depends on these measurements and the factors that may affect them. We carried out two studies; the first assessed the correlation between plasma renin concentration (PRC) and renin activity (PRA) and the agreement between them using two anticoagulants (EDTA and lithium heparin). The second evaluated ...

The index case, a 26-year-old man, presented with a 15-month history of gynaecomastia. Investigations revealed a large left-sided adrenal mass that secreted oestrone and oestradiol, with suppression of FSH, LH and testosterone production. It was removed in 1991 with correction of the hormonal abnormalities and follow-up has shown no recurrence to date.In April 2001 the eighteen-month old daughter of the index case developed greasy skin, acne, pubic hair...

Background Polycystic ovary syndrome (PCOS) affects between 5-10% of premenopausal women and is characterised by insulin resistance. PCOS also carries with it an increased lifetime risk of diabetes, hypertension and possibly coronary heart disease. The underlying mechanisms are unknown but we have proposed that metabolic insulin resistance may be associated with endothelial dysfunction, leading to increased vascular stiffness, abnormalities of fibrinolysis and increased platel...

The key enzymes in the terminal stages of human adrenal gland corticosteroid biosynthesis are aldosterone synthase (AS) and 11beta-hydroxylase (11beta-OHase). Their amino acid sequences differ by only 7% but they exhibit markedly different enzymatic activities. AS is expressed solely in the zona glomerulosa and converts 11-deoxycorticosterone (DOC) to aldosterone whereas 11beta-OHase is expressed mainly in the zona fasciculata and produces cortisol from 11-deoxycortisol. The 3...

Background: The CYP11B1 (11β-hydroxylase) and CYP11B2 (aldosterone synthase) genes are found in close proximity on human chromosome 8 and are highly polymorphic, enabling the definition of two common haplotypes. Haplotype1 includes the -344T and the Intron2 conversion polymorphisms in CYP11B2 and also the -1889T, -1859G polymorphisms in the regulatory region of CYP11B1. We and others have shown that these associate with increased aldosterone pr...

Aldosterone synthase (CYP11B2) and 11beta-hydroxylase (CYP11B1) genes are highly homologous in their coding regions (95%), lie in tandem approximately 40kb apart in human chromosome 8, and may have arisen from gene duplication. The pattern of linkage disequilibrium (LD) of this region in a population is determined not only by the distribution of recombination events but also by demographic factors determining the amount of random genetic drift. There is suggestiv...

The corticosteroids aldosterone and cortisol are implicated in the aetiology of hypertension. The CYP11B1 and CYP11B2 genes encode 11β-hydroxlylase and aldosterone synthase; polymorphisms across the CYP11B1/B2 locus are associated with increased aldosterone production, inefficient 11β-hydroxlation and hypertension. While polymorphisms located in the promoter region of both genes may alter transcription factor binding, other variants located in th...

Surgery is the most effective way of treating morbid obesity. The laparoscopic gastric bypass (Roux en-Y) is the preferred bariatric surgical procedure performed at our hospital. This combines restriction of intake with a profound sensation of early satiety.Ideally, multi-disciplinary team involvement (including psychological assessment), over a period of at least six months, is a prerequisite for bariatric surgery referral. The more psychotherapeutic wo...