Endocrine Abstracts

Annexin-1 (Anx-1), a 37 kDa protein, is a member of the super-family of Ca2+and phospholipid-binding annexin proteins and acts as a mediator of glucocorticoid (GC) action in the host defence and neuroendocrine systems. In the anterior pituitary Anx-1 is expressed mainly by folliculostellate (FS) cells and mediates the early-delayed feedback inhibition exerted by GCs on the release of ACTH and other pituitary hormones.The stress responsiveness ...

Acknowledgements: This work was generously supported by the Wellcome TrustAnnexin 1 (ANXA1) plays an important role in mediating the negative feedback effects of glucocorticoids on the HPA axis. It is released from non-secretory folliculostellate (FS) cells by glucocorticoids and acts locally to suppress ACTH release from corticotrophs. Previous studies suggest that the steroid-induced translocation of ANXA1 across the FS cell membrane is effected via me...

Annexin 1 (ANXA1) plays an important role in mediating the negative feedback effects of glucocorticoids on the HPA axis. In the anterior pituitary gland ANXA1 is localised mainly to the non-secretory folliculostellate (FS) cells. It is released from these cells by glucocorticoids and acts locally to suppress ACTH release from corticotrophs. Functional and histological studies suggest that the steroid-induced translocation of ANXA1 across the FS cell membrane is effected via me...

Annexin-1 (Anx-1), a 37kDa protein, is a member of the super-family of Ca2+- and phospholipid-binding annexin proteins and acts as a mediator of glucocorticoid (GC) action in the host defence and neuroendocrine systems. In the anterior pituitary Anx-1 is expressed mainly by folliculostellate (FS) cells and mediates the early delayed feedback inhibition exerted by GCs on the release of ACTH and other pituitary hormones.The role of Anx-1 in the ...

VEGF (vascular endothelial growth factor) is an endothelial cell mitogen responsible for physiological and pathophysiological angiogenesis. Abnormal regulation of VEGF expression in anterior pituitary folliculostellate (FS) cells has been implicated in pituitary tumour progression. PACAP is a well-documented stimulant of VEGF secretion from the pituitary in which both FS and endocrine cells express VEGF. TtT/GF cells are a mouse pituitary cell line with many characteristics of...

Annexin 1 (ANXA1) is a member of the annexin family of phospholipid- and calcium- binding proteins with a well-demonstrated role in the inhibitory actions of glucocorticoids on the release of ACTH, TSH, GH and PRL from the anterior pituitary. ANXA1 and ANXA1 truncated peptides have also recently been found to mimic glucocorticoid suppression of LH release (John et al, 2003 J Neuroendocrinol 15, 946-57). Here we test the hypothesis that because ANXA1 mediates some of the inhibi...

Hypogonadism is difficult to confirm with standard assays. A large proportion of testosterone (T) is bound to sex hormone binding globulin (SHBG) and is biologically inert. Accurate measures of free and biological-available-testosterone (Bio-T) are largely unavailable. In this study we compared formulae calculated from the total testosterone (TT) and SHBG in their ability to predict hypogonadism and/or Bio-T.TT and SHBG were determined by ELISA and Bio-T...

It has been postulated that ACTH might modulate its own secretion by a negative feedback loop and we have recently found that the ACTH receptor (MC2R) is present in both normal and tumorous human corticotrophs. In this study we investigated the expression of the ACTH receptor in mouse and rat pituitary tissue as well as mouse pituitary tumour (AtT20) cells and studied the effect of Synacthen (ACTH [1-24]) on ACTH secretion, cAMP release and cell proliferation in AtT20 cells. M...

It has been noted that there are differences in the hypothalamic-pituitary-adrenal (HPA) axis between the sexes, as well as changes in the axis with age. The differences in the HPA axis between the gender and age groups are thought to be due to differences in the efficiency of glucocorticoid (GC) negative feedback. The pituitary, a principle site of GC negative feedback, is the focus of this investigation. Annexin-1 (ANXA1) is a member of the annexin family of phospholipid- an...

BACKGROUNDAngina and Myocardial infarction have been reported in hyperthyroidism. Intense coronary artery spasm can be life threatening as it can lead to ventricular fibrillation and haemodynamic instability as reported in this patient.CASE HISTORYA 45-year-old lady was admitted with a history of head aches, palpitations, diarrhoea and weight loss. She was subsequently found to have thyrotoxicosis with the th...