Endocrine Abstracts

Agouti-related protein (AgRP) is a 132 amino acid protein, expressed in the brain where it antagonises the anorexic effect of alpha-MSH through melanocortin 3 and 4 receptors. In situ hybridisation and RT-PCR have shown that AgRP mRNA is also expressed in the steroidogenic zone of the adrenal cortex where levels are up-regulated following 24 hrs of fasting. However, its physiological significance in the adrenal gland is still unknown.To investigate the s...

Orexins are hypothalamic peptides known to stimulate food intake. Recently, orexins have been shown to activate the HPA axis at a central level1. We have previously shown that during late pregnancy the responsiveness of the HPA axis to a range of stressors is attenuated and suggested that the corticotropin releasing hormone (CRH) neurones or pathways impinging on them are less responsive2. If the CRH neurones themselves are less responsive, they should al...

Ghrelin, an endogenous growth hormone secretagogue receptor agonist, increases food intake, growth hormone (GH) and adrenocorticotrophic hormone (ACTH) following intracerebroventricular (ICV) and systemic administration. We now show that low dose intraperitoneal (ip) ghrelin (1nmol) stimulates feeding and results in a plasma ghrelin concentration not significantly different to 24-hour fasting levels. Following injection into 8 hypothalamic nuclei, ghrelin (30pmol) potently sti...

Ghrelin is a novel growth hormone-releasing peptide, recently identified in the rat stomach as the endogenous ligand for the growth hormone secretagogue-receptor (GHS-R). Previously, regulation of GH release was thought to occur primarily via a phasic interaction between two hypothalamic neuropeptides, GHRH and somatostatin. It is now thought that ghrelin is an important third factor in the regulatory pathway. In addition to its GH-releasing activity ghrelin may have other act...

In the rat hippocampus, corticosteroids modulate neuronal excitability. Glucocorticoid excess within the rat hippocampus results in a neurodegenerative effect, although corticosteroids also protect oligodendrocytes from cytokine-mediated apoptosis. Other studies have shown that systemically insignificant levels of aldosterone affect systemic blood pressure when administered icv. Previously, we have shown by RT-PCR and immunohistochemistry that the genes for 11beta-hydroxylase ...

During the search for the serine protease that cleaves pro-gamma-melatropin to stimulate adrenal growth (Bicknell et al, Cell, 2001, 105: 903), we identified another novel protease which we called AmP. In situ hybridisation detected AmP transcripts in steroidogenic tissues such as the brain particularly in the PVN and the dentate gyrus, in leydig cells of the testis, in underdeveloped follicles in the ovary as well as in the adrenal cortex. Full length cloning identified two s...

Perinatal glucocorticoid (GC) treatment accelerates lung maturation but may compromise health in adulthood, possibly via changes in hypothalamo-pituitary adrenal (HPA) activity. This study used western blot analysis and a well established in vitro method to investigate the effects of perinatal GC treatment on the expression and function of annexin 1 (ANXA1), a 37kDa protein which mediates facets of GC action in the neuroendocrine and host defence systems. Male rats were treate...

Lanreotide (LAN) Autogel, a new aqueous preparation of lanreotide acetate, was administered by deep sc injection every 4 weeks to patients with acromegaly (54 males, 53 females, mean age 53 plus/minus 1 year) who had previously been responsive to im SR LAN 30 mg microparticles. Patients who had been treated with at least 4 im injections of SR LAN 30 mg every 14 (49%), 10 (32%) or 7 days (20%) for at least 3 months and had a mean GH level <10 ng/ml, were switched to LAN Auto...

Galainin-like peptide (GALP) is a recently identified hypothalamic neuropeptide expressed in the arcuate nucleus. It is structurally related to galanin, GALP amino acid residues 9-21 are identical to the N terminal 1-13 residues of galanin. GALP binds to galanin receptors with high affinity but has greatest affinity to the GAL R2 receptor. Galanin has previously been demonstrated to significantly increase food intake when administered into the third ventricle or the paraventri...