Study on the significance and control mechanism of apoptosis in follicle atresia system

本课题旨在研究细胞凋亡在卵泡闭锁系统中的意义及其调控机制，主要研究了细胞凋亡的关键酶白细胞介素1 β转换酶（ICE）的存在、ICE在体内、体外排卵系统中的变化、ICE的体外调控因素、ICE在卵泡闭锁系统中的调控作用、ICE在卵泡闭锁系统中的调控作用、ICE在卵泡闭锁系统中的调控作用、ICE在卵泡闭锁系统中的调控作用以及ICE在卵泡闭锁系统中的调控作用。方法：1）测定大鼠卵巢及其培养体系中ICE mRNA的表达。2）PMSG-hCG处理组卵巢ICE mRNA表达无明显变化，但在hCG处理后6 h即开始增加，24 h达到高峰，24 h后又开始下降，24 h后下降，24 h（治疗前增加152%），48小时后恢复至治疗前水平。3）GnRH，雄激素和TNF-α刺激卵巢ICE mRNA表达（分别为对照组的140%、160%和200%）。以上结果表明：（1）ICE是Fas配体系统中细胞凋亡发生的关键酶，在卵巢中存在;（2）ICE与排卵系统密切相关;（3）促卵泡闭锁中促凋亡因子GnRH、雄激素和TNF-α均能刺激ICE的表达。提示ICE系统介导的细胞凋亡过程在卵泡闭锁系统中起重要作用。

In the present project, to study on the significance and control mechanism of apoptosis in follicle atresia system, I investigated (1) the existence of interleukin-1 beta converting enzyme (ICE), which is a key enzyme of apoptosis, (2) the changes of ICE in ovulation system in vivo and in vitro, (3) the control factor of ICE in vitro, using measurement of ICE mRNA in rats ovaries and its culture system.1) ICE mRNA was detected in rat ovaries. Its amount in ovary was 10% of that in spleen.2) In PMSG-hCG treatment, ICE mRNA in ovary was not changed in PMSG injection, but its appearance increased immedately 6 hours after hCG injection, reached to the peak 24 hours after (152% increase of pre-treatment), and retured to pre-treatment level 48 hours after.3) GnRH, androgen and TNF-alph atimulated ICE mRNA expression in ovary (140%, 160% and 200% of control, respectiveky). However, dexamethasone inhibited ICE mRNA expression (60% of control).In conclusion, I demonstrated that (1) ICE, which is a key enzyme of appearane of apoptosis in Fas-Fas ligand system, exists in ovary, (2) ICE is deeply concerned with ovulation system, (3) GnRH, androgen and TNF-alph, which are reported as stimulating factors of apoptosis in follicle atresia, stimulate ICE expression in ovary. These data indicate that apoptosis process via ICE system has important roles in follicle atresia system.