Akerlund Mats
Department of Obstetrics and Gynecology, University Hospital, S-221 85 Lund, Sweden.
Prog Brain Res. 2002;139:359-65. doi: 10.1016/s0079-6123(02)39030-7.
Important sources of oxytocin and vasopressin in the human, apart from the supraoptic and paraventricular nuclei of the brain, may be the fetus during labor as well as the endometrium and decidua of the uterus itself. The release of oxytocin and vasopressin to plasma is under influence of ovarian steroids. The two hormones stimulate uterine contractions in pregnant and non-pregnant women via myometrial oxytocin and vasopressin V1a receptors. At the onset of human labor preterm or at term no clear rise in the maternal plasma concentration of oxytocin and/or vasopressin has been demonstrated, but there may be an increased pulse frequency of the release of oxytocin to plasma with the advance of labor. Vasopressin is more potent than oxytocin on isolated myometrium from women undergoing Cesarean section at term. The myometrial concentration of the two receptors is about equal. At the onset of labor preterm and at term there is a tendency to an increase in the density of oxytocin and vasopressin V1a receptors, but there may be a heterogeneous expression of at least the former receptor between different myometrial cells. In advanced labor or after oxytocin treatment the receptors are markedly downregulated. The importance of oxytocin and vasopressin in mechanisms of preterm labor is confirmed by the therapeutic effect in the condition of the oxytocin and vasopressin V1a receptor blocking oxytocin analogue, atosiban. In women with primary dysmenorrhea the plasma concentration of vasopressin is elevated. The in vivo effect of vasopressin on uterine activity in non-pregnant women is about five times more pronounced than that of oxytocin, and it increases premenstrually. Correspondingly, the density of vasopressin V1a and oxytocin receptors vary to the same degree, and a premenstrual rise in the former receptor is seen. Atosiban and the non-peptide compound, SR 49059, which binds to the two receptors in a similar way as atosiban, are therapeutically effective in dysmenorrhea.
除了脑内的视上核和室旁核外，人体内催产素和血管加压素的重要来源可能是分娩时的胎儿以及子宫自身的子宫内膜和蜕膜。催产素和血管加压素释放到血浆中受卵巢甾体激素的影响。这两种激素通过子宫肌层的催产素和血管加压素V1a受体刺激孕妇和非孕妇的子宫收缩。在人类早产或足月分娩开始时，母体血浆中催产素和/或血管加压素浓度并未显示出明显升高，但随着分娩进展，催产素释放到血浆中的脉冲频率可能会增加。血管加压素对足月剖宫产妇女的离体子宫肌层的作用比催产素更强。两种受体在子宫肌层中的浓度大致相等。在早产和足月分娩开始时，催产素和血管加压素V1a受体密度有增加的趋势，但至少前一种受体在不同子宫肌层细胞之间可能存在异质性表达。在分娩后期或催产素治疗后，受体会明显下调。催产素和血管加压素V1a受体阻断催产素类似物阿托西班在早产机制中的治疗作用证实了它们在早产机制中的重要性。在原发性痛经女性中，血管加压素的血浆浓度升高。血管加压素对非孕妇子宫活动的体内作用比催产素明显约强五倍，且在月经前增加。相应地，血管加压素V1a和催产素受体密度以相同程度变化，且前者受体在月经前升高可见。阿托西班和非肽化合物SR 49059，其与阿托西班以类似方式结合这两种受体，在痛经治疗中有效。
