Yimu San improves obstetric ability of pregnant mice by increasing serum oxytocin levels and connexin 43 expression in uterine smooth muscle

Abstract

Prolonged farrowing remains one of the critical challenges in intensive pig farming. This study aims to explore the effects and mechanism of Yimu San (YMS), a Chinese veterinary medicine micro mist, on delivery ability with mouse models. Thirty-two pregnant mice were randomly divided into a control group and low-YMS, med-YMS, and high-YMS groups. The labor process time and stillbirth rate were recorded, the levels of serum oxytocin and prostaglandin E₂ (PGE₂) were measured with enzyme-linked immunosorbent assay (ELISA). Contractility measurements of the isolated uterus and the expression of connexin 43 (Cx43) in uterine smooth muscle were evaluated. The results showed that compared with the control group, the birth process time and stillbirth rate in the med-YMS and high-YMS groups were remarkably lower. The in vitro uterine contractions, levels of oxytocin, PGE₂, and Cx43 in the med-YMS and high-YMS groups were significantly higher than those in the control group. The differences of the above measurements between the low-YMS group and the control group were not obvious. It can be speculated that YMS could significantly promote labor in pregnant mice by enhancing the levels of oxytocin, Cx43, and PGE₂.

概要

目 的

评价益母散对孕鼠分娩能力的促进作用, 并初步探讨其作用机制。

创新点

首次在临近分娩小鼠中证明新中兽医药处方益母散可明显促进孕鼠分娩能力, 且此作用与催产素 和子宫平滑肌缝隙连接蛋白 43 (Cx43) 的高表达 相关。

方 法

将妊娠小鼠分为对照组和益母散低、 中、 高剂量组, 产前 3 天持续灌胃, 统计孕鼠分娩产程和死胎率。 采用离体平滑肌张力试验测定子宫平滑肌张力, 用酶联免疫吸附测定 (ELISA) 方法检测血清中催产素和前列腺素 E₂ (PGE₂) 含量, 用蛋白免疫印迹 (Western blotting) 及免疫组织化学等方法检测小鼠子宫平滑肌中 Cx43 含量。

结 论

益母散灌服处理能够使小鼠分娩产程缩短和死胎率降低 (图1), 并增强分娩小鼠子宫平滑肌张力 (图2) 。 ELISA 实验结果显示, 益母散灌服处理使分娩小鼠血清催产素水平显著提高 (图3) 。 免疫组化和免疫印迹实验结果显示, 益母散灌服处理使分娩小鼠子宫平滑肌 Cx43 含量显著提高 (图4 和5) 。 综上所述, 益母散具有提高孕鼠分娩能力的作用, 该作用与催产素水平和子宫平滑肌 Cx43 的高表达相关。