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Bradykinin Receptor (bradykinin + receptor)
Selected AbstractsNew insights into hereditary angio-oedema: Molecular diagnosis and therapyAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 3 2010Nikoletta Nagy ABSTRACT Hereditary angio-oedema (HAE) is a rare but potentially life-threatening condition. Three types are now recognized. Types I and II HAE involve mutations in the C1NH (SERPING1) gene, encoding the C1 inhibitor protein, whereas type III HAE involves mutations in the F12 gene, encoding coagulation factor XII (Hageman factor). They share a common final pathway leading to increased bradykinin formation. HAE must be distinguished from acquired angio-oedema with C1 esterase inhibitor deficiency, angiotensin-converting enzyme inhibitor-induced angio-oedema and the much more common histaminergic angio-oedema, occurring with or without weals. Understanding the pathogenesis of HAE is leading to the introduction of new therapies that target the bradykinin receptor or inhibit kallikrein activity, innovations that will hopefully reduce morbidity and mortality in this group of severe genetic disease. [source] Identification and characterisation of GPR100 as a novel human G-protein-coupled bradykinin receptorBRITISH JOURNAL OF PHARMACOLOGY, Issue 5 2003Katrin Boels G-protein-coupled receptor 100 (GPR100) was discovered by searching the human genome database for novel G-protein-coupled peptide receptors. Full-length GPR100 was amplified from a cDNA library of the neuroendocrine cell line BON, which is derived from a human pancreas carcinoid. The open-reading frame, present on a single exon, coded for a protein of 374 amino acids with highest sequence identity (43%) to the human orphan somatostatin- and angiotensin-like peptide receptor. The analysis of chromosomal localisation mapped the GPR100 gene to chromosome 1q21.2,q21.3. The stable expression of GPR100 in Chinese hamster ovary cells together with aequorin as calcium sensor and the promiscuous G-protein subunit ,16 as signal transducer revealed bradykinin and kallidin as effectors to elicit a calcium response. Dose,response curves yielded EC50 values for both ligands in the low nanomolar range, while the respective analogues without arginine at the carboxy-terminus were inactive. Calcium mobilisation was inhibited by the phospholipase C blocker U73122, but not by pertussis toxin, suggesting the involvement of the G-protein subunit ,q and not ,i or ,o in signal transduction. In line with the main function of kinins as peripheral hormones, we found that GPR100 was expressed predominantly in tissues like pancreas, heart, skeletal muscle, salivary gland, bladder, kidney, liver, placenta, stomach, jejunum, thyroid gland, ovary, and bone marrow, but smaller amounts were also detected in the brain and in cell lines derived from tumours of various origins. British Journal of Pharmacology (2003) 140, 932,938. doi:10.1038/sj.bjp.0705521 [source] Bradyzide, a potent non-peptide B2 bradykinin receptor antagonist with long-lasting oral activity in animal models of inflammatory hyperalgesiaBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2000Gillian M Burgess Bradyzide is from a novel class of rodent-selective non-peptide B2 bradykinin antagonists (1-(2-Nitrophenyl)thiosemicarbazides). Bradyzide has high affinity for the rodent B2 receptor, displacing [3H]-bradykinin binding in NG108-15 cells and in Cos-7 cells expressing the rat receptor with KI values of 0.51±0.18 nM (n=3) and 0.89±0.27 nM (n=3), respectively. Bradyzide is a competitive antagonist, inhibiting B2 receptor-induced 45Ca efflux from NG108-15 cells with a pKB of 8.0±0.16 (n=5) and a Schild slope of 1.05. In the rat spinal cord and tail preparation, bradyzide inhibits bradykinin-induced ventral root depolarizations (IC50 value; 1.6±0.05 nM (n=3)). Bradyzide is much less potent at the human than at the rodent B2 receptor, displacing [3H]-bradykinin binding in human fibroblasts and in Cos-7 cells expressing the human B2 receptor with KI values of 393±90 nM (n=3) and 772±144 nM (n=3), respectively. Bradyzide inhibits bradykinin-induced [3H]-inositol trisphosphate (IP3) formation with IC50 values of 11.6±1.4 nM (n=3) at the rat and 2.4±0.3 ,M (n=3) at the human receptor. Bradyzide does not interact with a range of other receptors, including human and rat B1 bradykinin receptors. Bradyzide is orally available and blocks bradykinin-induced hypotension and plasma extravasation. Bradyzide shows long-lasting oral activity in rodent models of inflammatory hyperalgesia, reversing Freund's complete adjuvant (FCA)-induced mechanical hyperalgesia in the rat knee joint (ED50, 0.84 ,mol kg,1; duration of action >4 h). It is equipotent with morphine and diclofenac, and 1000 times more potent than paracetamol, its maximal effect exceeding that of the non-steroidal anti-inflammatory drugs (NSAIDs). Bradyzide does not exhibit tolerance when administered over 6 days. In summary, bradyzide is a potent, orally active, antagonist of the B2 bradykinin receptor, with selectivity for the rodent over the human receptor. British Journal of Pharmacology (2000) 129, 77,86; doi:10.1038/sj.bjp.0703012 [source] |