Moohan J M, Lindsay K S
Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom.
Fertil Steril. 1995 Jul;64(1):160-5.
To determine if a discontinuous Percoll density gradient selects spermatozoa with different motion characteristics than direct swim-up.
Controlled prospective study of the effect of two preparation techniques on spermatozoa from normal semen samples using computer-aided sperm analysis (CASA).
The Fertility laboratory, Queen Charlotte's Hospital, London, United Kingdom.
Eighteen male patients.
Semen samples were divided into two equal parts. The first part was prepared by a direct swim-up whereas the other half was subjected to a three-layer discontinuous Percoll density gradient centrifugation. The separated samples were then examined at 30 minutes and 3, 6, and 24 hours by CASA.
Although swim-up selected a higher proportion of motile spermatozoa, Percoll produced a greater yield of motile cells. Straight line velocity was similar for both methods throughout study. In contrast, spermatozoa isolated by Percoll exhibited a significantly higher curvilinear velocity and amplitude of lateral head displacement, which lasted for > or = 6 hours. These changes were accompanied by a significant reduction in linearity of progression. The most dramatic effect of Percoll was to produce significantly greater numbers of spermatozoa expressing hyperactivation. After both swim-up and Percoll there was a decline in progressive motility over the 24 hours, although this was only significant for swim-up.
In normal semen, a discontinuous Percoll density gradient selects spermatozoa with better motion characteristics, more hyperactivation, and improved longevity compared with direct swim-up. In view of the relationship between sperm motion characteristics and fertilizing ability, we conclude that the three-layer discontinuous Percoll density gradient be adopted as the preferred method for the preparation of spermatozoa for assisted reproduction.
确定不连续的 Percoll 密度梯度法所筛选出的精子是否具有与直接上游法不同的运动特征。
采用计算机辅助精子分析（CASA），对两种制备技术对正常精液样本中精子的影响进行对照前瞻性研究。
英国伦敦夏洛特女王医院生育实验室。
18 名男性患者。
精液样本分成两等份。第一份采用直接上游法制备，另一半则进行三层不连续 Percoll 密度梯度离心。然后在 30 分钟以及 3、6 和 24 小时时，通过 CASA 对分离出的样本进行检测。
尽管上游法筛选出的活动精子比例更高，但 Percoll 法产生的活动细胞产量更高。在整个研究过程中，两种方法的直线速度相似。相比之下，通过 Percoll 法分离出的精子表现出明显更高的曲线速度和头部侧向位移幅度，且这种情况持续≥6 小时。这些变化伴随着前进线性的显著降低。Percoll 法最显著的效果是产生了大量表达超活化的精子。上游法和 Percoll 法处理后，24小时内前进运动能力均有所下降，不过仅上游法的下降具有统计学意义。
在正常精液中，与直接上游法相比，不连续的 Percoll 密度梯度法筛选出的精子具有更好的运动特征、更多的超活化现象以及更长的存活时间。鉴于精子运动特征与受精能力之间的关系，我们得出结论，三层不连续 Percoll 密度梯度法应作为辅助生殖中精子制备的首选方法。
