Büscher U, Chen F C, Riesenkampff E, von Dehn D, David M, Dudenhausen J W
Department of Obstetrics, Charité, Campus Virchow-Klinikum, Humboldt-University, Berlin, Germany.
Obstet Gynecol. 2001 Jul;98(1):117-21. doi: 10.1016/s0029-7844(01)01405-3.
To investigate dose-dependent effects of oxytocin receptor antagonist, atosiban, on oxytocin-induced contractions of myometrial strips from healthy pregnant women.
During elective cesareans, myometrial biopsies were taken from the lower uterine segment and trimmed into 2 x 2 x 10-mm longitudinal strips within 36 hours. One hundred twenty-two myometrial strips showed regular spontaneous contractions and were used for measurement. Each myometrial strip was mounted in a physiologic organ bath, and isometric contraction activity and contractile patterns were analyzed after stimulation with oxytocin. Frequency and amplitude of contractions and area under force-time curves were determined by adding atosiban at concentrations of 1, 5, 10, 20, 50, 100, 250, and 500 microg/mL. Resulting contraction activity (at least 20 contractions per concentration) was compared with reference activity.
Atosiban had significant inhibitory effects on myometrial contractions at concentrations as low as 1 microg/mL. Compared with reference activity (oxytocin stimulation only), resulting inhibition was higher than 50% with the lowest atosiban concentration used. This inhibition of contraction activity was dose-dependent and referred to the area under the curve, frequency, and amplitude of contractions. At high concentrations of atosiban, contraction activity was even lower than spontaneous activity without oxytocin stimulation.
The oxytocin receptor antagonist atosiban showed a significant, dose-dependent inhibition of oxytocin-induced contractions of human myometrium in vitro. It might be effective in tocolysis at term.
研究催产素受体拮抗剂阿托西班对健康孕妇子宫肌条催产素诱导收缩的剂量依赖性作用。
在择期剖宫产术中，从子宫下段取子宫肌层活检组织，并在36小时内修剪成2×2×10毫米的纵向肌条。122条子宫肌条呈现规则的自发收缩，用于测量。将每条子宫肌条安装在生理器官浴槽中，在用催产素刺激后分析等长收缩活动和收缩模式。通过添加浓度为1、5、10、20、50、100、250和500微克/毫升的阿托西班来确定收缩的频率、幅度和力-时间曲线下面积。将产生的收缩活动（每个浓度至少20次收缩）与对照活动进行比较。
阿托西班在低至1微克/毫升的浓度下对子宫肌层收缩具有显著的抑制作用。与对照活动（仅催产素刺激）相比，使用的最低阿托西班浓度导致的抑制率高于50%。这种对收缩活动的抑制是剂量依赖性的，涉及曲线下面积、收缩频率和幅度。在高浓度的阿托西班下，收缩活动甚至低于无催产素刺激时的自发活动。
催产素受体拮抗剂阿托西班在体外对人子宫肌层催产素诱导的收缩显示出显著的剂量依赖性抑制作用。它在足月时可能对抑制宫缩有效。
