Endocrine Abstracts

11Beta-Hydroxylase and aldosterone synthase catalyse the synthesis of corticosterone and aldosterone in the rat adrenal cortex and are encoded by the CYP11B1 and CYP11B2 genes respectively. These genes are also expressed in distinct regions of the CNS and cardiovascular system where they may play a key role in behavioural response and blood pressure homeostasis. However, it is unclear whether this extra-adrenal expression is regulated by, or contributes to, circulating levels ...

We present two patients with unusual manifestations of sarcoidosis and review gonadal involvement in this rare but important disease. A 27 year old man presented to the Ophthalmologists at our hospital with a red eye. He was diagnosed with anterior uveitis and commenced on topical corticosteroids. Following discovery of a testicular mass, he underwent testicular ultrasonography which demonstrated bilateral hyperechoic lesions. Histological examination of an open surgical biops...

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...

Backround: Androgenic anabolic steroids (AAS) are reported to increase cardiovascular risk by causing adverse changes in lipid profiles, impaired glucose tolerance, hyperhomocystinaemia and hypertension. Recent studies have also suggested impaired vascular reactivity in this group.Aim: To assess cardiovascular risk factors and arterial stiffness in AAS using and non-steroid using male bodybuilders and to compare them with healthy controls.Methods: Studies were conducte...

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...

Background: Although androgens are traditionally considered to be pro-atherogenic, there is increasing evidence to suggest an inverse relationship between testosterone and cardiovascular risk. Endothelial dysfunction is an early event in the process of atherogenesis and may occur as a result of vascular oxidative damage. In vivo, human monocytes release reactive oxygen intermediates as part of a normal immune response.Aim: This study assessed the contribution of testostero...