Gigli I, Byrd D D, Fortune J E
Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, T6-012B VRT, Ithaca, NY 14853, USA.
Theriogenology. 2006 Jul 15;66(2):344-53. doi: 10.1016/j.theriogenology.2005.11.021. Epub 2006 Jan 25.
Our laboratory developed a method for culturing small pieces of bovine and baboon ovarian cortex, rich in primordial follicles, that supports the initiation of follicle growth and development to the primary stage. However, only a few follicles progressed to the secondary stage. The purpose of the current experiments was to determine if changes in culture conditions, specifically oxygen concentration and supplements to the culture medium, would facilitate the primary to secondary follicle transition. In Experiment 1, ovarian cortical pieces from late-gestation bovine fetuses were cultured with 2, 5, 20, or 60% oxygen in Waymouth's medium plus ITS+ (insulin, transferrin, selenium plus linoleic acid and BSA). Although the three lower concentrations of oxygen were generally equivalent in promoting follicle activation and growth, the highest concentration (60%) had deleterious effects on follicle survival after 7 days in culture, reducing the number of healthy follicles to about 35% of the number observed with 20% oxygen (P<0.05). In Experiment 2, bovine ovarian cortical pieces were cultured in the standard gas mixture (5% CO(2) in air) with graded doses of fetal bovine serum (FBS, 2.5, 5, or 10%) in the presence or absence of 0.5 or 1x ITS+. All concentrations of FBS alone were much less effective at maintaining follicular health and supporting the initiation and progression of follicular growth than was ITS+. However, 5 and 10% FBS alone increased the percentage of healthy primordial and primary follicles by about twofold (P<0.05) in the absence of ITS+ and in the presence of 0.5x ITS+, they enhanced the primary to secondary follicle transition by 10- and 9-fold, respectively. Thus, of the culture conditions evaluated, 20% oxygen and medium containing 0.5x ITS+ plus 5% or 10% FBS were the most effective for promoting follicular health and development.
我们实验室开发了一种培养富含原始卵泡的小块牛和狒狒卵巢皮质的方法，该方法能支持卵泡生长并发育至初级阶段。然而，只有少数卵泡能发育到次级阶段。当前实验的目的是确定培养条件的变化，特别是氧气浓度和培养基添加物，是否会促进初级卵泡向次级卵泡的转变。在实验1中，将来自妊娠晚期牛胎儿的卵巢皮质块在含有2%、5%、20%或60%氧气的Waymouth培养基加ITS +（胰岛素、转铁蛋白、硒加亚油酸和牛血清白蛋白）中培养。尽管三个较低氧气浓度在促进卵泡激活和生长方面总体相当，但最高浓度（60%）在培养7天后对卵泡存活有有害影响，使健康卵泡数量减少至20%氧气条件下观察到数量的约35%（P<0.05）。在实验2中，将牛卵巢皮质块在标准气体混合物（空气中5%二氧化碳）中，在有或无0.5或1倍ITS +的情况下，用不同剂量的胎牛血清（FBS，2.5%、5%或10%）培养。单独使用所有浓度的FBS在维持卵泡健康以及支持卵泡生长的起始和进展方面远不如ITS +有效。然而，单独使用5%和10% FBS在无ITS +时使健康原始卵泡和初级卵泡的百分比增加了约两倍（P<0.05），在有0.5倍ITS +时，它们分别使初级卵泡向次级卵泡的转变增加了10倍和9倍。因此，在所评估的培养条件中，20%氧气以及含有0.5倍ITS +加5%或10% FBS的培养基对促进卵泡健康和发育最有效。
