Endocrine Abstracts

Background: Copeptin, the C-terminal part of the arginine vasopressin (AVP) precursor, is a 39-amino acid peptide stoichiometrically secreted with AVP in 1:1 ratio from the posterior pituitary. In contrast to AVP, copeptin remains stable ex vivo for several days in serum or plasma. Here, we investigated the use of the copeptin assay in the diagnostic workup of patients with suspected anterior pituitary dysfunction.Patients and methods: We measur...

Objective: Melatonin is a hormone secreted by the pineal gland which modulates sleep and wakefulness rhythms. Decreased melatonin secretion has been shown to be associated with increased daytime sleepiness and disturbed circadian rhythm in (irradiated) survivors of childhood craniopharyngeoma. The present study was performed to explore possible relationships between disturbed sleep, psychosocial impairment and melatonin secretion in patients treated with cranial radiotherapy a...

The transcription factor HIF-1α regulates hypoxia-mediated gene expression which promotes tumour growth, metastasis and desensitisation to chemo-and radiotherapy. HIF-1 is functional in a range of thyroid-carcinoma cells and is regulated by hypoxia and the PI3K and MAPK-signalling pathways.We aimed to determine if HIF-1 and PI3K were important in the development of a metastatic phenotype and play a role in desensitisation to radiotherapy in thyroid ...

The accurate measurement of cortisol by immunoassay is compromised by the potential for cross-reactivity of reagent antibodies with structurally-related steroid compounds present in patient serum. This susceptibility is potentiated when normal steroid metabolism is altered pharmacologically by anti-steroidogenic drugs. This class of drug is utilised in the management of Cushing’s syndrome to moderate cortisol production. To investigate the effect of the 11β-hydroxyla...

Multiple endocrine neoplasia 1 (MEN-1) is an inherited autosomal dominant tumour syndrome affecting mainly the parathyroid gland, pituitary and pancreas. Genetic defect appears to be deletion mutation of MEN1 gene coding for tumour suppression. We describe a case of MEN1 mosaic mutation never reported in the literature.The index case presented aged 52 in 1985 with headaches and dizziness when hypercalcemia of 3.2 mmol/l was noted. Past medical history in...

Unwanted late effects of cranial irradiation frequently include endocrine and psychosocial impairment, which may be overlooked in routine follow-up. The aim of the present study was to obtain systematic data on the long-term, psychosocial impairments of patients treated with cranial irradiation as compared to a non-irradiated control group. Both groups were fully hormone replaced including growth hormone (GH) substitution.A compilation of questionnaires ...

Prolactinomas are the commonest type of functioning pituitary adenoma in man. High circulating oestrogen levels are associated with lactotroph proliferation and increased PRL secretion essential for lactation. In vitro, oestradiol induces proliferation of the rat pituitary somatolactotroph GH3 cell line, and chronic oestrogen treatment of Fischer-344 rats in vivo results in lactotroph hyperplasia and adenoma formation, though the mechanisms responsible remain elu...

Background: Obesity is a major risk factor for the development of chronic diseases and a determinant of cardiovascular disease. Divergent associations between obesity and hormonal changes have been reported. The objective of the present study was to analyse the associations between different anthropometric measurements and serum hormone levels including insulin-like growth factor 1 (IGF-1), thyroid-stimulation hormone (TSH), prolactin, and testosterone.M...

Leptin acts not only as an anorexigenic hormone but is also involved in the regulation of cell-mediated immunity. However, since the impact of leptin on NK cells is currently elusive, we investigated the body weight-dependent leptin effects on NK cells numbers and function.In a first set of experiments leptin and MADB106 tumor cells were injected intravenously in male lean and diet-induced obese Lewis and F344 rats. In a second set of experiments an i...

Context: HIF-1α is frequently upregulated in many tumour types and has been shown to be critical for radio- and chemosensitivity in pre-clinical studies. However the regulation and function of HIF-1α is unknown in thyroid carcinomas.Objectives: Here, we evaluated basal expression and regulation of HIF-1α and target genes in primary thyroid carcinomas and in thyroid cancer cell lines (NPA, FTC-133, ARO).Design and out...