A potential mechanism of breakthrough bleeding associated with progestin: involvement in alteration of endometrial endothelial cells / 中国医学科学杂志(英文版)

ABSTRACT

<p><b>OBJECTIVE</b>To explore the potential mechanism of breakthrough bleeding associated with progestin with in vitro methods.</p><p><b>METHODS</b>The isolation and culture of human endometrial endothelial cells (HEECs) was performed with the method established in our laboratory. The content and activity of urokinase-type plasminogen activator (uPA) and the content of plasminogen activator inhibitor-1 (PAI-1) in cell supernatants after incubated with different concentrations of progesterone (0-5 micromol/L) and 17beta-estradiol (0, 0.1, or 1 nmol/L) were measured by method of ELISA. Apoptosis rate of HEECs was measured by flow cytometry. Viable cell count was measured by MTT.</p><p><b>RESULTS</b>The increased level of progesterone (0.5-5 micromol/L) combined with 17beta-estradiol elevated content and activity of uPA while the production of PAI-1 remained unchanged. The apoptosis of HEECs was inhibited along with the increment of total viable cell counts at higher concentrations of progesterone with 17beta-estradiol.</p><p><b>CONCLUSION</b>The inhibition of apoptosis and increased content and activity of uPA may contribute to the occurrence of irregular bleeding associated with progestin use to some extent</p>