title: Binding and signal transduction characteristics of the nonpeptide vasopressin V1A receptor-selective antagonist YM218 in cultured rat mesangial cells.
abstract: Vasopressin (AVP) causes mesangial cell contraction, proliferation and hypertrophy. The present study investigated the effects of YM218, a potent, nonpeptide AVP V(1A) receptor-selective antagonist, on rat mesangial cells using binding, signal transduction and cell growth assays. Specific binding of (3)H-AVP to rat mesangial cell plasma membranes was dependent upon time, temperature and membrane protein concentration. Scatchard plot analysis of equilibrium binding data revealed the existence of a single class of high-affinity binding sites with the expected V(1A) receptor profile. YM218 showed high affinity for V(1A) receptors, exhibiting a K(i) value of 0.19 nmol/l. AVP concentration-dependently increased intracellular Ca(2+) ([Ca(2+)](i)) levels, stimulated mitogen-activated protein (MAP) kinase and induced hyperplasia. Conversely, YM218 potently suppressed [Ca(2+)](i) elevation, activation of MAP kinase and hyperplasia induced by AVP. These results indicate that YM218 displays both high affinity for rat mesangial cell V(1A) receptors and high potency in inhibiting AVP-induced signal transduction and growth response. Therefore, YM218 is a useful pharmacologic tool for investigating the physiologic and pathophysiologic roles of AVP in kidney, and may have clinical application in the prevention or regression of mesangial cell growth.
authors.affiliation: Institute for Drug Discovery Research, Astellas Pharma Inc., 5-2-3 Toukoudai, Tsukuba, Ibaraki 300-2698, Japan. atsuo.tahara@jp.astellas.com
authors.forename: Atsuo
authors.initials: A
authors.lastname: Tahara
authors.forename: Junko
authors.initials: J
authors.lastname: Tsukada
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Tomura
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kusayama
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Momose
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Taniguchi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Takeyuki
authors.initials: T
authors.lastname: Yatsu
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shibasaki
mesh_terms: D000818:Animals; D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines / Q000494:pharmacology*; D001667:Binding, Competitive; D002118:Calcium / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D002478:Cells, Cultured; D008297:Male; D050527:Mesangial Cells / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D010880:Piperidines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D017483:Receptors, Vasopressin / Q000819:agonists; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: C501286:4'-(4,4-difluoro-5-(2-oxo-2-(4-piperidinopiperidino)ethylidene)-2,3,4,5-tetrahydro-1H-1-benzoazepine-1-carbonyl)-2-methyl-3-furanilide; D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines; D010880:Piperidines; D017483:Receptors, Vasopressin; D020929:Mitogen-Activated Protein Kinase Kinases; D002118:Calcium