Leibo S P, Giambernardi T A, Meyer T K, Bastias M C, Rogers B J
Rio Vista International, San Antonio, Texas.
Fertil Steril. 1990 May;53(5):906-12. doi: 10.1016/s0015-0282(16)53530-4.
To solve the logistical problems of the sperm penetration assay (SPA) to provide just a sufficient number of hamster ova exactly when they are needed, a new method to cryopreserve the ova has been devised. The ova, suspended in a 1.5 M solution of propylene glycol as a cryoprotectant in an isotonic salt solution, were frozen in 1/4 mL plastic straws. Included in each straw was a sucrose solution, isosmotic to the propylene glycol solution, to serve as an osmotic buffer during dilution of the cryoprotectant out of the ova. This one-step method of dilution permitted the ova to be recovered and diluted out of the cryoprotectant within the straw in which they had been originally frozen. A total of 547 cryopreserved ova were thawed, 504 (92.1%) of which were morphologically normal after they had been incubated at 37 degrees C for 3 hours. After removal of the zonae, the frozen-thawed ova were compared with fresh, control ova in SPAs of donor and patient semen that had been capacitated in TEST-yolk buffer. The percent penetration and penetration index of fresh versus cryopreserved ova did not differ significantly for either donor or patient semen.
为解决精子穿透试验（SPA）的后勤问题，即在需要时恰好提供足够数量的仓鼠卵子，已设计出一种冷冻保存卵子的新方法。将卵子悬浮于等渗盐溶液中含1.5M丙二醇作为冷冻保护剂的溶液中，装入1/4mL塑料细管中冷冻。每个细管中都含有一种与丙二醇溶液等渗的蔗糖溶液，在将冷冻保护剂从卵子中稀释出来的过程中作为渗透缓冲剂。这种一步稀释法可使卵子在其最初冷冻的细管内从冷冻保护剂中回收并稀释。总共解冻了547个冷冻保存的卵子，其中504个（92.1%）在37℃孵育3小时后形态正常。去除透明带后，将冻融卵子与在TEST-卵黄缓冲液中获能的供体和患者精液的新鲜对照卵子进行精子穿透试验比较。对于供体或患者精液，新鲜卵子与冻融卵子的穿透率和穿透指数差异均无统计学意义。
