Lefebvre R, Lo M C, Suarez S S
Department of Anatomy, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
Biol Reprod. 1997 May;56(5):1198-204. doi: 10.1095/biolreprod56.5.1198.
Sperm binding to oviductal epithelium probably serves to form the isthmic sperm reservoir. This interaction of sperm and oviductal epithelium may involve species-specific carbohydrate recognition. We tested a series of carbohydrates and glycoproteins for inhibition of bovine sperm binding to oviductal epithelium in vitro. Explants of isthmic and ampullar epithelium were obtained from oviducts that had been surgically removed from preovulatory heifers. The explants were incubated (39 degrees C, 5% CO2) with fetuin, asialofetuin, ovalbumin, fucoidan, fucose, N-acetyl glucosamine, or N-acetyl glucosamine sulfate dissolved in a modified Tyrode's balanced salt solution, termed sperm-TALP (pH 7.4, 295 mOsm) for 10 min before frozen-thawed motile sperm obtained by swim-up were added. After 15 min, the explants were rinsed, and sperm binding density was evaluated. Oviductal explants treated with fucoidan (3 mg/ml; p < 0.001, n = 5) or fucose (31 mM, p < 0.01, n = 6) had reduced densities of bound sperm compared to the controls. Incubation of explants in increasing concentrations of fucose (4-62 mM) resulted in increased inhibition of sperm binding. Pretreating explants with fucosidase also reduced sperm binding (p < 0.001, n = 3) compared to that in controls containing the fucosidase inhibitor deoxyfuconojirimycin. The presence of fucosylated molecules on the surface of the oviductal epithelium was confirmed by labeling with fucose lectins from Ulex europeus and Lotus tetragonolobus. We conclude that fucose is involved in a specific interaction between bovine sperm and oviductal epithelium.
精子与输卵管上皮的结合可能有助于形成峡部精子储存库。精子与输卵管上皮的这种相互作用可能涉及物种特异性的碳水化合物识别。我们测试了一系列碳水化合物和糖蛋白对体外牛精子与输卵管上皮结合的抑制作用。峡部和壶腹部上皮的外植体取自从排卵前小母牛手术切除的输卵管。将外植体在39℃、5%二氧化碳条件下与溶解在改良的泰勒氏平衡盐溶液（称为精子-TALP，pH 7.4，295 mOsm）中的胎球蛋白、去唾液酸胎球蛋白、卵清蛋白、岩藻依聚糖、岩藻糖、N-乙酰葡糖胺或N-乙酰葡糖胺硫酸盐孵育10分钟，然后添加通过上浮法获得的冻融活动精子。15分钟后，冲洗外植体，并评估精子结合密度。与对照组相比，用岩藻依聚糖（3 mg/ml；p < 0.001，n = 5）或岩藻糖（31 mM，p < 0.01，n = 6）处理的输卵管外植体结合精子的密度降低。将外植体在浓度不断增加的岩藻糖（4 - 62 mM）中孵育导致精子结合抑制增加。与含有岩藻糖苷酶抑制剂脱氧岩藻糖诺吉霉素的对照组相比，用岩藻糖苷酶预处理外植体也降低了精子结合（p < 0.001，n = 3）。通过用来自欧洲荆豆和四角百脉根的岩藻糖凝集素标记，证实了输卵管上皮表面存在岩藻糖基化分子。我们得出结论，岩藻糖参与了牛精子与输卵管上皮之间的特异性相互作用。
