摘要
Felid spermatozoa are sensitive to cryopreservation-induced damage, but functional losses can be mitigated by post-thaw swim-up or density gradient processing methods that selectively recover motile or structurally-normal spermatozoa, respectively. Despite the importance of sperm energy production to achieving fertilization, there is little knowledge about the influence of cryopreservation or post-thaw processing on felid sperm metabolism. We conducted a comparative study of domestic cat and cheetah sperm metabolism after cryopreservation and post-thaw processing. We hypothesized that freezing/thawing impairs sperm metabolism and that swim-up, but not density gradient centrifugation, recovers metabolically-normal spermatozoa. Ejaculates were cryopreserved, thawed, and processed by swim-up, Accudenz gradient centrifugation, or conventional washing (representing the ‘control’). Sperm glucose and pyruvate uptake, lactate production, motility, and acrosomal integrity were assessed. Mitochondrial membrane potential (MMP) was measured in cat spermatozoa. In both species, lactate production, motility, and acrosomal integrity were reduced in post-thaw, washed samples compared to freshly-collected ejaculates. Glucose uptake was minimal pre- and post-cryopreservation, whereas pyruvate uptake was similar between treatments due to high coefficients of variation. In the cat, swim-up, but not Accudenz processing, recovered spermatozoa with increased lactate production, pyruvate uptake, and motility compared to controls. Although confounded by differences in non-specific fluorescence among processing methods, MMP values within treatments were positively correlated to sperm motility and acrosomal integrity. Cheetah spermatozoa isolated by either selection method exhibited improved motility and/or acrosomal integrity, but remained metabolically compromised. Collectively, findings revealed a metabolically-robust subpopulation of cryopreserved cat, but not cheetah, spermatozoa, recovered by selecting for motility rather than morphology.
摘要译文
Felid精子对低温保存造成的损伤敏感，但是功能损失可以通过解冻游泳或密度梯度处理方法分别选择性地恢复活动的或结构正常的精子来减轻。尽管精子能量产生对获得受精的重要性，但对冷冻保存或解冻后处理对于精子代谢的影响知之甚少。我们对冷冻保存后的家猫和猎豹精子代谢进行了比较研究。我们假设冷冻/解冻会损害精子代谢，而游泳起来，而不是密度梯度离心，可以恢复代谢正常的精子。射精被冻存，解冻并通过游泳，Accudenz梯度离心或常规洗涤（代表“对照”）进行处理。精子葡萄糖和丙酮酸摄取，乳酸生产，运动性，和顶体完整性进行了评估。在猫精子中测量线粒体膜电位（MMP）。在这两个物种中，乳酸生产，动力，和顶体完整性在解冻后，洗净的样本与新鲜收集的射精相比减少。葡萄糖摄取在冷冻保存前和冷冻保存后是最小的，而由于高变异系数，处理之间丙酮酸盐摄取是相似的。在猫，游泳，但不是Accudenz处理，恢复精子乳酸产量增加，丙酮酸摄取和运动相比。尽管加工方法中非特异性荧光的差异使其困惑，处理内的MMP值与精子活力和顶体完整性呈正相关。通过选择方法分离的猎豹精子表现出提高的运动性和/或顶体完整性，但仍保持代谢受损。总的来说，研究结果显示代谢强大的冷冻猫的亚群，但不是猎豹，精子，通过选择动力而不是形态恢复。
Kimberly A. Terrell[a][b]; David E. Wildt[a]; Nicola M. Anthony[b]; Barry D. Bavister[c]; S.P. Leibo[b][d]; Linda M. Penfold[e]; Laurie L. Marker[f]; Adrienne E. Crosier[a]. Different patterns of metabolic cryo-damage in domestic cat (Felis catus) and cheetah (Acinonyx jubatus) spermatozoa ☆[J]. Cryobiology, 2012,64(2): 110–117