Zupkó I, Márki A, Gáspár R, Falkay G
Department of Pharmacodynamics, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Mol Hum Reprod. 1998 Sep;4(9):921-4. doi: 10.1093/molehr/4.9.921.
The spontaneous uterine motor activity of the post-partum rat was investigated in parallel with the in-vitro determination of the density of the alpha1 and beta-adrenergic receptors of the myometrium. The in-vivo experiments were performed by an improved method, using a Millar catheter fitted with a latex microballoon. The spontaneous contractility of the post-partum rat uterus was found to be highest 24 h after delivery, indicating that this time is the most suitable for pharmacological examinations of tocolytic agents. A very close correlation was found between the results of the in-vivo experiments and the alpha1/beta-adrenergic receptor ratio assessed by an in-vitro receptor assay, thus indicating that the state of the adrenergic receptor system fundamentally determines the contractility of the uterus. This conclusion is supported by the fact that the pharmacological sensitivity of the rat uterus to prazosin and fenoterol changed as a function of the post-partum time in accordance with the alpha1/beta-adrenoceptor ratio. These results and the relevant data available reveal a crucially important role of an alpha1-adrenoceptor-mediated process, implicating alpha1-blockers as theoretically potent agents for inhibition of premature uterine contractions.
对产后大鼠子宫的自发运动活性进行了研究，并同时对子宫肌层α1和β肾上腺素能受体的密度进行了体外测定。体内实验采用改良方法，使用装有乳胶微球囊的Millar导管进行。发现产后大鼠子宫的自发收缩性在分娩后24小时最高，这表明这段时间最适合进行宫缩抑制剂的药理学检查。体内实验结果与通过体外受体测定评估的α1/β肾上腺素能受体比率之间发现了非常密切的相关性，因此表明肾上腺素能受体系统的状态从根本上决定了子宫的收缩性。大鼠子宫对哌唑嗪和非诺特罗的药理敏感性随产后时间的变化与α1/β肾上腺素能受体比率一致，这一事实支持了这一结论。这些结果以及现有的相关数据揭示了α1肾上腺素能受体介导过程的至关重要的作用，这意味着α1阻滞剂在理论上是抑制子宫过早收缩的有效药物。
