American journal of obstetrics and gynecology
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Am. J. Obstet. Gynecol. · Dec 1994
Receptors for and myometrial responses to oxytocin and vasopressin in preterm and term human pregnancy: effects of the oxytocin antagonist atosiban.
Our purpose was to study myometrial oxytocin and type V1 vasopressin receptors, the in vitro contractile effects of these hormones, and the influence of an oxytocin antagonist. ⋯ The effect of oxytocin on the myometrium in pregnancy is mediated by an oxytocin receptor, whereas vasopressin acts on both oxytocin and vasopressin receptors. The initiation of labor both preterm and at term may be primarily related to increased release of oxytocin, which is locally produced in the uterus and not detectable in the plasma, but oxytocin and vasopressin receptors may play a role in the regulation of labor. The analog 1-deamino-2-D-Tyr(OEt)-4-Thr-8-Orn-oxytocin, which blocks both the oxytocin and the V1 vasopressin receptor, should inhibit labor both preterm and at term, the former confirming results of recent clinical studies in Sweden and the United States.
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Am. J. Obstet. Gynecol. · Dec 1994
Effect of oxytocin antagonists on the activation of human myometrium in vitro: atosiban prevents oxytocin-induced desensitization.
Our purpose was to investigate whether the sensitivity of myometrial cells to oxytocin is affected by prolonged exposure to oxytocin antagonists. ⋯ Atosiban is a pure oxytocin antagonist and has a specific, reversible effect on myometrial cells in vitro. Its potential use for the management or even prevention of idiopathic preterm labor or to reverse uterine hypertony during oxytocin-induced labor should be tested in controlled clinical trials.