Endocrine Abstracts

Background: The enzymes 11beta-hydroxylase and aldosterone synthase are key control steps in regulation of cortisol and aldosterone synthesis. We have previously reported that polymorphic variation of the gene encoding aldosterone synthase (CYP11B2) is associated with altered efficiency of 11b-hydroxylation of the precursor of cortisol, deoxycortisol. In order to examine this relationship in greater detail, we have studied the pattern of steroid precursor metabolite excretion ...

Aldosterone synthase catalyses the synthesis of aldosterone in the adrenal cortex and is encoded by the CYP11B2 gene. Recent studies have shown that CYP11B2 is also expressed in the central nervous system (CNS) but little is known about its regulation. In this study, we have quantitated CYP11B2 expression in the CNS following dietary manipulation of sodium and infusion of angiotensin II.In study 1, 3 groups of male WKY rats (n=6) were fed normal (0.3%), high (3%) or low (0...

INTRODUCTIONThe plasma concentrations and urinary excretion rates of 18-OH-F and 18-oxo-F are high in Conn's syndrome and glucocorticoid suppressible hyperaldosteronism, reputedly because aldosterone synthase (AS) has abnormal access to cortisol (F). However, both compounds are also excreted in normal subjects. Two enzymes, 11beta-hydroxylase (11OH) and AS, located in the zona fasiculata (ZF) and zona glomerulosa (ZG) respectively, are capable of 18-hydroxylation but only ...

Aldosterone synthase and 11beta-hydroxylase catalyse the final steps of glucocorticoid (corticosterone) and mineralocorticoid (aldosterone) production in the rat adrenal cortex. They are encoded by the CYP11B2 and CYP11B2 genes respectively. Recent studies have shown that CYP11B1 and CYP11B2 are also expressed in the brain, the vascular system and the heart where it has been suggested that aldosterone influences cardiac function and plays a role in cardiac fibrosis. However, i...

Background: Cortisol availability to target tissues represents a complex interplay of synthesis, secretion, metabolism and excretion. A number of these processes are regulated by enzymes that are encoded by genes that are key candidates in determining the metabolic and cardiovascular phenotype in man. Measurement of a range of corticosteroid metabolites allows the activity of these enzymes to be inferred. We have studied the pattern of cortisol metabolite excretion in a large ...

Aldosterone synthase catalyses the synthesis of the mineralocorticoid aldosterone in the adrenal zona glomerulosa and is encoded by the CYP11B2 gene. Recent studies have shown that CYP11B2 is also expressed in the cardiovascular system. CYP11B2 expression in the adrenal gland is regulated by the renin-angiotensin system and potassium. However, little is known about its expression in other tissues. In this study, we have quantitated CYP11B2 expression in the cardiovascular syst...

Glucocorticoid remediable aldosteronism (GRA) was first described in 1966 by Sutherland et ala. In this family, aldosterone secretion was regulated by ACTH and symptoms and signs were reversed by the administration of exogenous glucocorticoid. GRA is usually characterised by moderate to severe hypertension with early onset. The hypertension is often difficult to control and is associated with greatly increased vascular risk. It is inherited as an autosomal dominant trait and ...

Members of a hospital staff (n=332) were invited to complete a survey outlining dietary and lifestyle behaviour, and indicate if they were interested in a weight management programme. Height and weight were measured and body mass index (BMI) was calculated, in all respondents.Two hundred and sixty (78%) staff members responded, 60 males (23.1%) and 200 females (76.9%). The mean age of respondents was 36.5 yrs (35.8yrs males, 36.7yrs female). The mean bo...

Objectives: Aldosterone synthase catalyses the synthesis of aldosterone in the adrenal zona glomerulosa and is encoded by the CYP11B2 gene. Recent studies have shown that the CYP11B2 gene is also expressed in the rat central nervous system (CNS), particularly the cerebellum and hippocampus, suggesting local corticosteroid production. The renin-angiotensin system regulates the expression of the CYP11B2 gene in the adrenal cortex. However, little is k...

Introduction: MicroRNA (miRNA) has been shown to post-transcriptionally regulate physiological systems modulating blood pressure, including the adrenal biosynthesis of aldosterone. This raises the possibility that levels of specific miRNAs circulating in plasma might reflect these functional effects and have diagnostic value in the identification of hypertension and its various underlying causes. In a previous study, we measured plasma levels of miRNAs originating from the miR...