绵羊发情周期中VEGF在卵巢中的表达

Expression of VEGF in ovary of ovine through the estrous cycle

应用免疫组化方法结合计算机图像分析技术,分析同期发情后0、5、9、12、15d的绵羊卵巢中血管内皮生长因子(Vascular endothelial growth factor,VEGF)表达强度变化,以期了解VEGF在绵羊卵巢发情周期不同时期的表达规律。结果显示:VEGF阳性目标主要出现于卵泡膜与颗粒细胞。原始卵泡、初级卵泡、次级卵泡VEGF表达依次增强(P<0.05)。发情周期0～5d,大窦腔卵泡(颗粒细胞4～8层)VEGF表达量骤然上升(P<0.05),而9d开始显著下降,与5d比较差异显著(P<0.05)。12d继续下降(P<0.05)且为最低值,15d又明显上升(P<0.05)。VEGF在卵巢间质呈弱表达,各个时期之间差异不显著(P>0.05)。结果表明,绵羊卵巢存在着血管周期性新生的变化特点,而VEGF在这种周期性血管新生过程中起着重要的调控作用。

Vascular endothelial growth factor（VEGF） has the role of stimulating the proliferation of epithelial cells and angiogenesis. It plays an important regulatory role in the course of female reproduction,including follicular development,oocyte maturation,corpus luteum formation and function and so on. This study combined immunohistology and computer graphic analytical technique to investigate the dynamic changes of VEGF on the ovarian of ovine that collected each on 0,5,9,12 and 15 d, to approach the laws of VEGF changes through the estrous cycle in ovary of ovine. VEGF-positive targets were mainly seen in the follicular theca and granulosa cells. The expression of VEGF in primordial follicles, primary follicles, secondary follicles were gradually enhanced （P 〈 0.05）. The expression of VEGF in antral follicles （4-8 layers of granulosa cell） was sharply increased （P^0.05） through 0-5 d of estrous cycle,but 9 d it were lower obviously （P〈0.05） comparing with 5 d ,however it is higher than 0 d （P〈0.05）. 12 d is continued to decline and significant difference comparing with 9 d （P〈0.05）. At this time it was the lowest value. But it was significantly increased at 15 d （P〈0.05）. The expression of VEGF in the ovarian interstitium was minor and in each stage of estrous cycle was not significant difference （P〈0.05）. The result shows that there was changing of angiogenesis in ovary of ovine during estrous cycle and VEGF in this cyclical process of angiogenesis plays an important regulatory role.