PDF(Pubmed)
Abstract：
Sperm cryopreservation is an important tool for genetic diversity management programs and the conservation of endangered breeds and species. The most widely used method of sperm conservation is slow freezing, however, during the process, sperm cells suffer from cryoinjury, which reduces their viability and fertility rates. One of the alternatives to slow freezing is vitrification, that consist on rapid freezing, in which viable cells undergo glass-like solidification. This technology requires large concentrations of permeable cryoprotectants (P- CPA\'s) which increase the viscosity of the medium to prevent intracellular ice formation during cooling and warming, obtaining successful results in vitrification of oocytes and embryos. Unfortunately, this technology failed when applied to vitrification of sperm due to its higher sensitivity to increasing concentrations of P-CPAs. Alternatively, a technique termed \'kinetic sperm vitrification\' has been used and consists in a technique of permeant cryoprotectant-free cryopreservation by direct plunging of a sperm suspension into liquid nitrogen. Some of the advantages of kinetic vitrification are the speed of execution and no rate-controlled equipment required. This technique has been used successfully and with better results for motility in human (50-70% motility recovery), dog (42%), fish (82%) and donkey (21.7%). However, more studies are required to improve sperm viability after devitrification, especially when it comes to motility recovery. The objective of this review is to present the principles of kinetic vitrification, the main findings in the literature, and the perspectives for the utilization of this technique as a cryopreservation method.
摘要：
精子冷冻保存是遗传多样性管理计划和濒危品种和物种保护的重要工具。最广泛使用的精子保存方法是缓慢冷冻，然而,在这个过程中,精子细胞遭受冷冻损伤，这降低了他们的生存能力和生育率。缓慢冷冻的替代方法之一是玻璃化，包括快速冷冻，其中活细胞经历玻璃状凝固。该技术需要高浓度的渗透性冷冻保护剂（P-CPA），这增加了介质的粘度，以防止在冷却和升温过程中形成细胞内的冰，在卵母细胞和胚胎的玻璃化中获得成功的结果。不幸的是,由于该技术对P-CPA浓度增加的敏感性较高，因此应用于精子玻璃化时失败。或者，已经使用了一种称为“动力精子玻璃化”的技术，该技术包括通过将精子悬浮液直接浸入液氮中来进行无渗透性冷冻保护剂冷冻保存的技术。动力学玻璃化的一些优点是执行速度和不需要速率控制的设备。该技术已被成功使用，并在人体中具有更好的运动效果（50-70％的运动恢复），狗(42%)鱼(82%)和驴(21.7%)。然而,需要更多的研究来改善失透后的精子活力，尤其是在运动恢复方面。这篇综述的目的是介绍动力学玻璃化的原理，文献中的主要发现，以及将该技术用作冷冻保存方法的前景。
