Effect of NO on the expression of VEGF and its receptors in mouse uterus during peri-implantation
Zhang-Xuan; Wang-Hong-Mei; Qian-Dong; Lin-Hai-Yan; Liu-Guo-Yi; Li-Qing-Lei; Zhu-Cheng
Acta Zoologica Sinica 50(1): 55-61
2004
ISSN/ISBN: 0001-7302
Accession: 011990190
Nitric oxide (NO) is believed to play a pivotal role in embryo implantation. Successful embryo implantation depends upon the synchronized roles of hormones and a series of cytokines, and this event is accompanied by angiogenesis. As an angiogenic and vascular permeability factor, vascular endothelial growth factor (VEGF) is essential for endometrium development and placental vascular function during early pregnancy. The purpose of this study was to investigate the effect of NO on VEGF and its receptors, as well as the mechanism of NO during mouse implantation using intrauterine injection, in situ hybridization, and western blotting techniques. Nitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME) was administered with or without sodium nitroprusside (SNP), NO donor, into one uterine horn on day 3 of pregnancy, and the contralateral uterine horn served as the control. We collected the uteri on days 5, 6, and 7 of pregnancy and examined the expression of VEGF and its receptors. The results showed that, compared with the control, the expression of VEGF and its receptors mRNAs declined in L-NAME-treated uteri during peri-implantation. Similarly, the western blotting results indicated that the protein levels of VEGF and its receptors decreased during peri-implantation. The L-NAME-mediated effect on the expression of VEGF and its receptors reversed when SNP was co-administered with L-NAME. These data suggested that inhibition of NO production regulated the expression of VEGF and its receptors during peri-implantation, which may have serious consequences on embryo implantation.