Oxytocin and Oxytocin Antagonist Metabolism in the Plasma of Pregnant Women.
- Author:
Tae Hun AN
1
;
Sok Cheon PAK
;
Tae Gyu AHN
Author Information
1. Department of Anesthesiology College of Medicine, Chosun University, Kwangju, Korea.
- Publication Type:In Vitro ; Original Article
- Keywords:
Oxytocin;
Oxytocin antagonist;
Uterus;
Pregnant women;
Preterm labor
- MeSH:
Cystinyl Aminopeptidase;
Female;
Humans;
Metabolism*;
Obstetric Labor, Premature;
Oxytocin*;
Plasma*;
Pregnancy;
Pregnant Women*;
Radioimmunoassay;
Radioligand Assay;
Uterine Contraction;
Uterus
- From:Korean Journal of Obstetrics and Gynecology
2002;45(6):921-925
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
OBJECTIVE: Oxytocin antagonists maybe useful in inhibiting the uterine contractions of preterm labor. One such compound is TT-235. The purpose of this study was to compare the resistance of TT-235 and oxytocin to enzymatic degradation by oxytocinase in pregnant human. METHODS: Blood samples from pregnant women not in labor were incubated in vitro with known amounts of oxytocin and TT-235. Samples were collected at 0, 15, 30, 45 and 60 minute intervals for oxytocin analysis and at 0, 10, 60 and 360 minutes for TT-235 analysis. Oxytocin was analyzed by radioimmunoassay after extraction while TT-235 was analyzed by radioreceptor assay. RESULTS: In human blood, oxytocin was readily metabolized with greater than 83% disappearance over the 60 minute incubation period. In contrast, TT-235 was stable up to 360 minutes of incubation. CONCLUSION: This study suggests that: (1) blood from pregnant human does contain oxytocinase at least in vitro; and (2) TT-235 was resistant to enzymatic degradation by human blood, implying that this oxytocin antagonist may have prolonged activity in vivo in humans.
