Endocrine Abstracts

Antipsychotic induced hyperprolactinaemia, mediated by blockade of dopamine D2 receptors, is much more common than prolactinoma in patients receiving antipsychotic medication. We present two cases of the latter.Case 1: A 47-year-old gentleman with depression treated with amitriptyline, fluoxetine and risperidone presented with headaches and a left sided visual field defect. Pituitary MRI showed a 2 cm macroadenoma abutting the optic chiasm. Prolactin was...

Standard Autonomic Function tests AFT may not detect subclinical CAN. Modalities exist (Frequency Domain) using PSA of HRV, which may detect subclinical CAN.We performed standard AFTs (HR response to deep breathing, Valsalva, Tilt at 1 min and 6 min) and PSA of HRV on these tests in 46 subjects (29 DM and 17 Controls) matched for age and sex. We sought to establish if those DM subjects considered normal by AFT would exhibit abnormalities in PSA of HRV. W...

BackgroundSR141716 (Rimonabant) has been shown to significantly inhibit food intake and reduce body weight in rodents and humans by antagonising CB1 receptors. The gut hormones peptide YY3–36 (PYY3–36) and oxyntomodulin (OXM), released from L-cells in the small intestine inhibit food intake in both rodents and humans and this effect is thought to be mediated via the hypothalamus.Objective<...

Thyroid hormones play a major role in the metabolic function of mammalian cells and are of particular importance in the development of the fetal brain. The MCT8 gene has recently been shown to encode an active and specific thyroid hormone transporter. Recent reports have identified mutations in the MCT8 gene in several unrelated boys presenting with severe X-linked psychomotor retardation and elevated serum T3.Ontogeny of mRNA encoding MCT8 was examined ...

The causal relationship between obesity and heart failure is broadly acknowledged; however, the pathophysiological mechanisms involved remain unclear. Besides hemodynamic changes, an alternative mechanism of cardiomyocytes apoptosis secondary to intracellular lipid accumulation has been proposed. However, this seems to be valid only for severe obesity but may not explain the increase in heart failure risk with mild-to-moderate overweight. Since adipocytes secrete a wide variet...

Alteration of sympathetic nervous system (SNS) activity may be involved in the development of obesity. Among stimuli which may activate the SNS, stress is often quoted. Responses to stressors include stimulation of the hypothalamo-pituitary-adrenal axis (HPA) and of the SNS, which result in increased plasma cortisol and catecholamines concentrations. Although the stress response seems to be automatic (therefore not subject to regulation), studies in human have highlighted the ...

Energy balance is controlled by the arcuate nucleus through integration of peripheral hormonal signals such as leptin, ghrelin, peptide YY (PYY) and glucagon like peptide 1 (GLP-1). The commonest reason for young women in the developed world to be underweight is restrictive anorexia nervosa (AN). Constitutionally thinness (CT) has been described in young women who satisfies the WHO definition for moderate to severe underweight (BMI 13–16.9 kg/m2). CT women have...

The mineralocorticoid hormone aldosterone is secreted by the adrenal cortex. It plays a major role in maintaining water and electrolyte balance and hence blood pressure homeostasis by the kidneys. The aldosterone synthesizing zona glomerulosa of the adrenal cortex is a highly vascularized region. This allows a complex and articulated interaction between the steroidogenic cells and the vascular endothelial cells regulating the hormonal output.In this stud...

Dehydroepiandrosterone (DHEA) and its sulphate ester DHEAS are neurosteroids with potential effects on neurogenesis, neuronal survival and neuronal stem cells proliferation. DHEA is produced by the inner adrenocortical zone, which is in direct contact to the adrenomedullary chromaffin. Unlike the closely related sympathetic neurons, chromaffin cells are able to proliferate throughout the life span. The aim of the present study was to examine in vitro the effect of DHEA ...

The increased appetite associated with hyperthyroidism is assumed to be secondary to an increased metabolic rate. However, the role of thyroid hormones in appetite regulation is poorly understood. We hypothesised that thyroid hormones directly regulate food intake and studied the effects of peripheral and CNS administration of tri-iodothyronine (T3) on food intake in male Wistar rats in vivo.A single subcutaneous (s.c.) injection of 4.5 nmol per ...