Endocrine Abstracts

The pathogenesis of gonadotrophin secreting pituitary tumours (gonadotrophinomas) remains poorly understood. Bone morphogenetic proteins (BMPs) are important for the control of cell proliferation and differentiation and BMP2 is essential for commitment of undifferentiated pituitary cells to the gonadotroph cell lineage. In addition, BMPs have been implicated in tumourigenesis in a variety of tissues, associated with up-regulated expression of Id (Inhibitors of differentiation)...

The ubiquitous transcription factor, CREB, is responsible for mediating gene transcription in many endocrine tissues. Recent studies reveal that the activation of several signalling pathways can lead to the phosphorylation of CREB at Ser133, including PKC, MAPKs, CaMKs, and PI3K. In the pituitary gonadotroph, there are consensus cAMP response elements (CREs) in several of the gonadotrophin subunit promoters as well as in the GnRH receptor promoter. We have previously shown tha...

C-type natriuretic peptide (CNP) is encoded by the Nppcgene and is abundant in the hypothalamus and anterior pituitary gonadotrophs. Nppc deletion leads to skeletal deformity, dwarfism, early death and female infertility. To investigate regulation of Nppcexpression and action in the hypothalamic-pituitary-gonadal axis, we investigated transcriptional regulation of the Nppc promoter in alphaT3-1 gonadotroph cells by transient transfection of reporter...

Bone morphogenetic proteins (BMPs) regulate growth, differentiation and apoptosis in a variety of tissues and have crucial roles in the regulation of reproduction. BMPs bind specific Type II receptors and form complexes with Type I receptors (Alk2, 3 or 6) whereby the Type II receptors activate Type I receptors by phosphorylation. BMP2 and 4 play a crucial role in the development of the gonadotroph cell lineage during mouse pituitary morphogenesis and BMP6, 7, and 15 stimulate...

T3 and T4 rapidly activate intracellular signalling cascades via thyroid hormone receptor (TR)-independent actions, suggesting the existence of a plasma membrane receptor. Recent studies support a role for the RGD recognition site of integrin, a transmembrane glycoprotein, as a cell surface TR. We have demonstrated, using PCR and Western blotting, the expression of integrin αVβ3 mRNA and protein in the transformed human osteosarcoma cell line MG...

Background: Mutations in succinate dehydrogense-B (SDH-B) or von Hippel Lindau (VHL) genes can result in chromaffin tumours.Objective: To compare the clinical phenotypes of subjects developing chromaffin tumours as a result of SDH-B or VHL mutations.Subjects: Thirty-one subjects with chromaffin tumours. Sixteen subjects had SDH-B gene mutations and 15 subjects had a diagnosis of VHL.<p ...