血管紧张素在人子宫蜕膜化中的作用

ROLE OF ANGIOTENSINⅡON DECIDUALIZATION IN HUMAN ENDOMETRIUM

我们用放免测定和放射自显影证明人早孕蜕膜组织中存在免疫活性的血管紧张素Ⅱ和丰富的血管紧张素Ⅰ型受体。离体细胞培养实验显示 ,血管紧张素Ⅱ以剂量依赖方式刺激蜕膜细胞催乳素的分泌 ,而血管紧张素转换酶抑制剂对催乳素分泌似乎有微弱的抑制作用 ,但未显示统计学差异。以上结果表明AngⅡ可以促进人子宫蜕膜化反应 ,推测它在胚胎植入和妊娠维持中可能发挥重要的作用。

The AngⅡ levels and changes in human decidia at week 5～9 of gestation were measured by RIA and quantitative in vitro autoradiography was used to map the density of AngⅡreceptors (AngⅡR). The inhibition of [ 125 I] AngⅡbinding by subtype specific antagonist was used to examine AngⅡR subtypes. The effect of AngⅡ on PRL release in human decidual cells at early pregnancy was also observed. The results showed that (1) AngⅡcontent was 116 8±8 42 pg/g wet weight in decidual tissue collected week 5 of gestation. AngⅡlevels gradually increased as gestation proceeded. The highest value occurred in week 7 groups (7th w vs 5th w group P <0 01). (2) Considerable AngⅡR was detected in human decidual tissue at week 6～8 of gestation. The Ang Ⅱ subtypeⅠ(AT 1) receptor antagonist Losartant (Dup 753) caused substantial displacement, whereas the Ang Ⅱ subtypeⅡ(AT 2) receptor antagonist (PD 123319) did not cause detectable displacement. Thus the AT 1 receptor was the predominant receptor expressed in human decidua at the early stage of pregnancy. (3) AngⅡsignificantly stimulated PRL release in human decidual cells in a dose dependent mode. The inhibitor of AngⅡconverting enzyme (ACEI) induced the decrease of PRL secretion slightly. All the results indicated that AngⅡplays an important role in the deciduialization of human endometrium, and is involved in embryo implantation and the maintance of gestation.