Tajik P, Niwa K
Division of Animal Science and Technology, Faculty of Agriculture, Okayama University, Japan.
Theriogenology. 1998 Mar;49(4):771-7. doi: 10.1016/S0093-691X(98)00026-0.
Bovine cumulus-enclosed oocytes were matured in culture for 22 to 24 h, freed from cumulus cells and inseminated with frozen-thawed spermatozoa in a chemically defined medium containing 1 mg polyvinylalcohol/ml with or without 5 mM caffeine and/or 10 micrograms heparin/ml and 13.9 mM glucose. Penetration of oocytes was observed only in the medium containing caffeine and/or heparin. Regardless of the presence of glucose, similar proportions of oocytes were penetrated in the medium containing heparin with (73 and 83%) or without (36 and 41%) caffeine. However, when the medium was supplemented with caffeine only, a higher penetration rate was observed in the presence (41%) than in the absence (27%) of glucose. When oocytes inseminated in medium containing caffeine and heparin with or without glucose were cultured in a chemically defined, protein-free medium, 72 and 90% and 9 and 21% of inseminated oocytes developed to the > or = 2-cell and blastocyst stages 48 and 192 h post insemination, respectively. These results, obtained using chemically defined conditions, indicate that glucose is required for stimulating fertilization in vitro of bovine oocytes and that synergistic action of caffeine and heparin appears independently of the reversing activity of caffeine on the inhibition of heparin-induced sperm capacitation by glucose.
牛卵丘-卵母细胞复合体在培养液中成熟培养22至24小时，去除卵丘细胞后，在含有1毫克聚乙烯醇/毫升、添加或不添加5毫摩尔咖啡因和/或10微克肝素/毫升以及13.9毫摩尔葡萄糖的化学限定培养基中，与冻融精子进行受精。仅在含有咖啡因和/或肝素的培养基中观察到卵母细胞的穿透。无论葡萄糖是否存在，在含有肝素且添加（73%和83%）或不添加（36%和41%）咖啡因的培养基中，卵母细胞的穿透比例相似。然而，当培养基仅添加咖啡因时，在有葡萄糖（41%）存在时观察到的穿透率高于无葡萄糖（27%）时。当在含有或不含有葡萄糖的含有咖啡因和肝素的培养基中受精的卵母细胞在化学限定的无蛋白培养基中培养时，分别有72%和90%以及9%和21%的受精卵母细胞在受精后48小时和192小时发育至≥2细胞期和囊胚期。这些在化学限定条件下获得的结果表明葡萄糖是刺激牛卵母细胞体外受精所必需的，并且咖啡因和肝素的协同作用似乎独立于咖啡因对葡萄糖抑制肝素诱导精子获能的逆转活性。
