Molecular characterization of a cloned human oxytocin receptor.
We describe here the binding and functional properties of a cloned human oxytocin receptor (OTR). We established a transient OTR expression system on COS-1 cells, which do not express vasopressin receptors. With the transfected cells and [3H]oxytocin, the dissociation constant (Kd) of OTR to oxytocin was 6.0 +/- 1.1 nmol/l; the binding properties of several oxytocin-related peptides were also examined. The functional properties of OTR were determined by an electrophysiological method, using a Xenopus laevis oocyte injected with in vitro transcribed OTR mRNA. These two methods showed that [Phe2,Orn8]vasotocin, a vasopressin agonist, was an OTR antagonist. A combination of these methods using cloned OTR cDNA is a novel and effective method for the investigation of oxytocin-related ligands.
Kimura
T
T
Department of Obstetrics and Gynecology, Osaka University Medical School, Japan.
Makino
Y
Y
Saji
F
F
Takemura
M
M
Inoue
T
T
Kikuchi
T
T
Kubota
Y
Y
Azuma
C
C
Nobunaga
T
T
Tokugawa
Y
Y
D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis / Q000235:genetics*; D005260:Female; D006801:Humans; D009865:Oocytes / Q000737:chemistry / Q000166:cytology / Q000648:ultrastructure; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D018045:Receptors, Oxytocin / Q000032:analysis* / Q000235:genetics* / Q000502:physiology; D014316:Tritium; D014982:Xenopus laevis
D012333:RNA, Messenger; D018045:Receptors, Oxytocin; D014316:Tritium; D004247:DNA