Suarez S S, Katz D F, Owen D H, Andrew J B, Powell R L
Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0144.
Biol Reprod. 1991 Feb;44(2):375-81. doi: 10.1095/biolreprod44.2.375.
After insemination, mammalian sperm undergo a striking change in flagellar beat pattern, termed hyperactivation. In low-viscosity culture medium, nonhyperactivated sperm flagella generate relatively symmetrical, low-amplitude waves, while hyperactivated sperm flagella generate an asymetrical beating pattern that results in nonprogressive movement. Since sperm encounter highly viscous and viscoelastic fluids in the female reproductive tract, the progress of hyperactivated sperm was compared with that of nonhyperactivated and transitional sperm in media of increasing viscosity. Hamster sperm obtained from the caudal epididymis were incubated in a medium that promotes capacitation. After 0, 3, and 4 h of incubation, the majority of the sperm exhibited, respectively, activated, transitional, and hyperactivated motility. At each of these time points, aliquots of sperm were removed from incubation and added to solutions of 0, 5%, 10%, 20%, and 30% Ficoll in medium. Samples containing mostly hyperactivated sperm (4 h) maintained higher swimming and flagellar velocities and were able to generate greater forces in response to increased viscous loading than activated sperm (0 h). Transitional sperm (3 h) showed an intermediate response. The paths of hyperactivated sperm through solutions of 20% and 30% Ficoll were considerably straighter than those made through medium alone. This is the first demonstration that hyperactivation can confer a mechanical advantage upon sperm in the oviduct where they may encounter viscous oviductal fluid and a viscoelastic cumulus matrix.
授精后，哺乳动物的精子在鞭毛摆动模式上会发生显著变化，称为超活化。在低粘度培养基中，未超活化的精子鞭毛产生相对对称、低振幅的波动，而超活化的精子鞭毛则产生不对称的摆动模式，导致非前进性运动。由于精子在雌性生殖道中会遇到高粘性和粘弹性的液体，因此将超活化精子在粘度不断增加的培养基中的运动情况与未超活化和过渡态精子进行了比较。从附睾尾部获取的仓鼠精子在促进获能的培养基中孵育。孵育0、3和4小时后，大多数精子分别表现出活化、过渡和超活化运动能力。在每个时间点，从孵育液中取出等分试样的精子，加入含0%、5%、10%、20%和30%聚蔗糖的培养基溶液中。与活化精子（0小时）相比，主要含超活化精子的样本（4小时）在粘性负荷增加时能保持更高的游动速度和鞭毛摆动速度，并能产生更大的力量。过渡态精子（3小时）表现出中间反应。超活化精子在20%和30%聚蔗糖溶液中的游动路径比仅在培养基中的路径直得多。这首次证明了超活化能赋予精子在输卵管中机械优势，因为它们在输卵管中可能会遇到粘性的输卵管液和粘弹性的卵丘基质。
