Metritis is an important disorder in dairy cows during the early postpartum period. Myometrial contractility is a prerequisite for uterine involution; however, very scanty literature is available about the effect of metritis on this process and endocrine responsiveness. This study was aimed to evaluate the effect of inflammation on uterine contractility in vitro, and the inflammation was induced by incubating myometrial strips with lipopolysaccharides (LPS). Myometrial samples were collected from 17 healthy Holstein Friesian cows during caesarean section. Eight longitudinal strips from each cow were incubated in organ baths with LPS concentrations of 0 (LPS₀), 0.1 (LPS_0.1), 1 (LPS₁) and 10 µg/ml (LPS₁₀). Spontaneous contractility and contractility induced by increasing concentrations of oxytocin (10^–10 – 10^–7 mol/L) were recorded during nine 30‐min intervals (T1 to T9). The minimum amplitude (minA), maximum amplitude (maxA), mean amplitude (meanA) and area under the curve (AUC) were calculated for each time interval. LPS had an effect (p ≤ .05) on maxA, meanA and AUC. In T1, myometrial strips incubated with LPS_0.1 and LPS₁ had higher (p ≤ .05) maxA, meanA and AUC than the strips incubated with LPS₀. In T9 without oxytocin, LPS₀ led to higher (p ≤ .05) maxA, meanA and AUC than LPS_0.1 and LPS₁. In T8 and T9 with oxytocin, LPS₁ had lower (p ≤ .05) maxA, meanA and AUC than the other LPS concentrations. Interestingly, the results show that LPS has a transient positive effect on myometrial contractility in vitro and that this effect is dependent on LPS concentration and duration of incubation.

中文翻译：

---

脂多糖对牛子宫收缩力的体外作用

在产后早期，Metritis是奶牛的一种重要疾病。子宫肌层收缩是子宫复旧的先决条件。然而，关于子宫炎对这一过程和内分泌反应的影响的文献很少。这项研究旨在评估炎症对体外子宫收缩的影响，并且通过将子宫肌条与脂多糖（LPS）孵育来诱发炎症。剖宫产时从17头健康的荷斯坦黑白花奶牛收集子宫肌层样品。将每头母牛的八个纵向条带在器官浴中以LPS浓度分别为0（LPS ₀），0.1（LPS _0.1），1（LPS ₁）和10 µg / ml（LPS ₁₀）孵育。）。 在九个30分钟的间隔内（T1至T9）记录了催产素浓度（10 ^–10 – 10 ^–7 mol / L）引起的自发性收缩和收缩。计算每个时间间隔的最小幅度（minA），最大幅度（maxA），平均幅度（meanA）和曲线下面积（AUC）。LPS有一个效果（p 上MAXA，meanA和AUC≤0.05）。在T1中，用LPS孵育肌层条_0.1和LPS ₁具有更高（p  ≤0.05）MAXA，meanA和AUC比用LPS温育条带₀。在T9不催产素，LPS ₀导致了更高的（p  ≤0.05）MAXA，meanA和AUC比LPS _0.1和LPS ₁。在T8和T9与催产素，LPS ₁具有较低（p  ≤0.05）MAXA，meanA和AUC比其它LPS浓度。有趣的是，结果表明，LPS在体外对子宫肌层收缩具有短暂的积极影响，并且这种影响取决于LPS浓度和孵育时间。