Berlinguer F, Gonzalez-Bulnes A, Succu S, Leoni G, Mossa F, Bebbere D, Ariznavarreta C, Tresguerres J A F, Veiga-Lopez A, Naitana S
Department of Animal Biology, University of Sassari, Via Vienna 2, 07100 Sassari, Italy.
Domest Anim Endocrinol. 2007 May;32(4):303-14. doi: 10.1016/j.domaniend.2006.04.007. Epub 2006 May 2.
Previous research has reported evidence for negative effects of progestagens on follicular growth and oocyte competence. In the present study, negative effects of progestagens on follicular growth and oocyte developmental competence were assessed. During the breeding season, 20 Sarda ewes were treated with two doses of cloprostenol, 10 days apart, to assure the presence of a corpus luteum (CL). On day 5 after the second cloprostenol dose, 10 ewes were treated with a progestagen sponge while 10 females remained untreated. Starting on day 7 after the second cloprostenol dose, all the ewes were treated with 6 equal doses of 24 I.U. of FSH (Ovagen, ICP, NZ), every 12h. The number of follicles > or =2mm in diameter increased (P<0.0005) in all the ewes from 24 h before to 60 h after the first FSH dose (from 12.8+/-1.1 to 23.4+/-1.3 in treated and from 12+/-0.6 to 22+/-1.2 in untreated ewes, n.s.). There were no significant differences in follicle dynamics between groups, but concentrations of estradiol in control ewes were higher than in the progestagen group (P<0.05). Twelve hours after the last FSH dose, oocytes were collected by ovum pick-up. Recovery rates were lower for progestagen-treated ewes (71.1 versus 83%; P<0.001). After IVP procedure, cleavage rate was also lower in the progestagen group (39.1 versus 82.6%; P<0.001). Furthermore, blastocysts output revealed that oocyte developmental competence was lower in progestagen group (17.3 versus 30.4%; P=0.245), although differences were not significant. These results suggest deleterious effects from progestagen on oocyte developmental competence and set the basis for new protocols for in vitro embryo production.
先前的研究已报道了孕激素对卵泡生长和卵母细胞能力产生负面影响的证据。在本研究中，评估了孕激素对卵泡生长和卵母细胞发育能力的负面影响。在繁殖季节，对20只撒丁岛母羊每隔10天注射两剂氯前列醇，以确保黄体（CL）的存在。在第二次注射氯前列醇后的第5天，10只母羊用孕激素海绵进行处理，而10只母羊不进行处理。从第二次注射氯前列醇后的第7天开始，所有母羊每隔12小时接受6剂等量的24国际单位促卵泡素（Ovagen，ICP，新西兰）治疗。在所有母羊中，从首次注射促卵泡素前24小时到注射后60小时，直径≥2毫米的卵泡数量增加（P<0.0005）（处理组从12.8±1.1增加到23.4±1.3，未处理母羊从12±0.6增加到22±1.2，无显著差异）。两组之间卵泡动态没有显著差异，但对照母羊的雌二醇浓度高于孕激素处理组（P<0.05）。在最后一次注射促卵泡素12小时后，通过采卵收集卵母细胞。孕激素处理母羊的回收率较低（71.1%对83%；P<0.001）。在体外受精程序后，孕激素处理组的卵裂率也较低（39.1%对82.6%；P<0.001）。此外，囊胚产出显示孕激素处理组的卵母细胞发育能力较低（17.3%对30.4%；P=0.245），尽管差异不显著。这些结果表明孕激素对卵母细胞发育能力有有害影响，并为体外胚胎生产的新方案奠定了基础。
