行政院國家科學委員會補助專題研究計畫成果報告:巨噬細胞對假孕田鼠蛻膜瘤細胞凋亡扮演之角色

Apoptosis, a form of physiological death, is involved in the luteal regression. The Fas and FasL interaction is responsible for the apoptosis of follicular atresia and luteal regression. By using flow cytometry, the surface expression of Fas and FasL on the peritoneal exudate cells, predominantly macrophages, of cyclic and pregnant day 4 hamsters was studied. Fas expression on the peritoneal macrophages was increased when serum progesterone levels were low on cyclic day 3. Release of pituitary prolactin (PRL) was blocked by daily treatment with bromocriptine (BC) (1 mg s.c. given at 1000 h) on days 1 to 4 of pregnancy. PRL withdrawal induced functional luteolysis, as evidenced by a precipitous drop in serum progesterone to background levels. Expressions of Fas and FasL on the peritoneal macrophages of BC treated group were significantly increased. Thereupon, PRL are proved to support the corpus luteum and to regulate Fas and FasL expression on the peritoneal macrophages in early pregnancy.細胞凋亡是一種生理性死亡，已廣為認定其參與了黃體退化之過程。而Fas 是腫瘤壞死因子受器族群中之一種表面蛋白，與其受質FasL 結合後會引發細胞凋亡，此首見於免疫系統中品株移除和免疫耐受性之建立。Fas 和FasL 交互作用引發之細胞凋亡也見諸卯巢濾泡細胞退化或黃體退化。本實驗抽取呈現正常動情週期和懷孕田鼠之腹腔細胞，主要為巨噬細胞，利用流式細胞儀檢測其表面抗原Fas 及FasL 之表現。發現Fas 表現與血漿中助孕素含量之高低有關，在動情週期第三天黃體退化時，血漿中助孕素含量最低，此時腹腔巨噬細胞表面抗原Fas 表現顯著增加• 利用bromoCriPtine ( BC ）抑阻垂體泌乳素分泌，將懷孕田鼠由懷孕第一天至第四天，每天皮下注射0 . 2 毫升酒精與鹽水< 1 比l ＞混合液或含有1 毫克BC 之酒精與鹽水混合液。BC 處理組血漿中助孕素降至基礎值，除此功能性黃體退化外，腹腔巨噬細胞表面抗原Fas 及FasL 均明顯增加伊＜0 . 05 ）。本實驗發現腹腔巨噬細胞表面抗原Fas 及FasL 之表現隨血漿中助孕素含量之多寡變化外，也証明垂體泌乳素具有維持懷孕早期之黃體和調控腹腔巨噬細胞表面抗原Fas 及FasL 之表現