糖在猕猴精子低温冷冻保存过程中的作用

Function of Sugars During Cryopreservation of Rhesus Macaque (Macaca mulatta) Spermatozoa

TTE或TEST防冻液在冻存猕猴精子时产生不同结果 ,其主要不同在于防冻液中糖成分的不同。本实验利用透射电镜技术检测这 2种防冻液冻存的猕猴精子冷冻前后超微结构的变化 ,以说明糖在低温冻存过程中的作用。结果表明 ,冷冻复苏过程对精子结构产生了影响 ,TTE法低温保存的猕猴精子的头部的质膜出现少许皱褶或泡化现象 ,但精子的顶体、核或是精子尾部的结构与鲜精的结构基本相似。猕猴精子经TEST法低温保存后 ,大部分精子结构则发生了明显的变化 ,精子膜、顶体和精子核明显泡化、损伤或破裂 ,精子尾部不能分辨出正常的超微结构。这提示 ,可能由于TTE防冻液中复杂的糖成分在降温 /复苏过程对精子起到了较好的协同冷冻保护作用 ;而TEST防冻液中单一的糖成分不能完全保护精子避免低温损伤 ,低温保存过程破坏了精子的结构 ,并影响了复苏后精子体外存活能力与受精能力。

This study was conducted to evaluate the cryoprotective function of sugars in two freezing media (TTE and TEST) by comparing the spermatozoa morphologic change of rhesus monkey before and after cryopreservation using transmission electron microscopy. The results showed that the structure of acrosome integrity, nuclear and tail of most spermatozoa cryopreserved with TTE was similar with that of fresh spermatozoa, except for the slight swell of plasma membrane. However, in spermatozoa cryopreserved with TEST, the plasma membrane were fluctuated, swelled and broken, the acrosome integrity and nuclear were damaged, and the structure of tail were changed significantly. It demonstrated that TTE is a suitable freezing media for rhesus monkey spermatozoa cryopreservation. Sugars exert cryoprotective roles by protecting the intact of plasma membrane and acrosome integrity, but the protective roles of sugars are significant different.