Department of Obstetrics and Gynaecology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 102 Pokfulam Road, Pok Fu Lam, Hong Kong.
Reprod Biol Endocrinol. 2024 Nov 19;22(1):147. doi: 10.1186/s12958-024-01315-6.
Levonorgestrel (LNG) acts as an emergency contraceptive mainly by inhibiting or postponing ovulation. We carried out this study to investigate whether LNG at concentration relevant for emergency contraception (EC) affect ciliary beat frequency and muscular contraction of the human Fallopian tube, which might contribute additional actions for EC.
This was an in vitro experimental study on human Fallopian tube tissue collected from ten women undergoing hysterectomy. The tubal explants were cultured in vitro, primed with oestradiol and progesterone at concentrations resembling the physiological early luteal phase, and treated with LNG at 0, 1, 10 and 100 ng/ml concentrations. Ciliary beat frequency was measured from the tubal epithelial strips, and the basal tone, amplitude and frequency of contractions were recorded from longitudinal smooth muscle strips. These parameters at different LNG concentrations were compared against the control (LNG 0 ng/ml).
Treatment of tubal tissue strips with LNG at all concentrations studied did not significantly alter the ciliary beat frequency nor basal muscle tone (p > 0.05 for both) compared with control. Significant reduction in the amplitude and frequency of tubal muscular contractions was shown after treatment with LNG only at 100 ng/ml (p < 0.05 for both) but not lower concentrations (p > 0.05) compared with control.
LNG did not significantly inhibit ciliary beat frequency and muscular contraction of the human Fallopian tube at the doses used for EC, suggesting that the Fallopian tube is unlikely a target for the EC action of LNG.
左炔诺孕酮（LNG）作为紧急避孕药的主要作用机制是抑制或延迟排卵。我们进行这项研究旨在探讨紧急避孕相关浓度的 LNG 是否会影响人输卵管的纤毛摆动频率和肌肉收缩，这可能为紧急避孕提供额外的作用机制。
这是一项在体外进行的人类输卵管组织实验研究，从 10 名接受子宫切除术的女性中采集输卵管组织。将输卵管外植体在体外培养，用类似于生理早黄体期的浓度的雌二醇和孕酮预刺激，并分别用 0、1、10 和 100ng/ml 的浓度处理 LNG。从输卵管上皮条测量纤毛摆动频率，从纵向平滑肌条记录基础张力、收缩幅度和频率。将这些参数与对照（LNG 0ng/ml）进行比较。
与对照相比，所有研究浓度的 LNG 处理均未显著改变纤毛摆动频率或基础肌肉张力（两者均为 p>0.05）。仅在用 100ng/ml LNG 处理后观察到输卵管肌肉收缩的幅度和频率显著降低（两者均为 p<0.05），而在较低浓度（p>0.05）下没有观察到这种降低。
在用于紧急避孕的剂量下，LNG 对人输卵管的纤毛摆动频率和肌肉收缩没有显著抑制作用，这表明输卵管不太可能是 LNG 紧急避孕作用的靶器官。
