Ellington J E, Samper J C, Jones A E, Oliver S A, Burnett K M, Wright R W
Department of Veterinary Comparative Anatomy, Pharmacology and Physiology, Washington State University, Pullman 99164, USA.
Anim Reprod Sci. 1999 May 17;56(1):51-65. doi: 10.1016/s0378-4320(99)00030-5.
Formation of a spermatozoa ('sperm') reservoir in the mare is thought to occur through lectin-mediated sperm attachment to the oviductal epithelium. Once attached, prefertilization sperm survival is supported by oviductal factors. Cryopreservation of stallion sperm decreases the number of sperm attaching to oviduct epithelial cells (OEC) and the length of time these sperm survive. Quantification of in vitro interactions between sperm and OEC in a co-culture system may provide an assay for functional integrity of cryopreserved or fresh sperm samples. Additionally, superior additives for in vitro handling of stallion sperm may be isolated from OEC secretory products. Experiment 1 compared first service conception (FSC) rates resulting from the use of cryopreserved sperm of seven stallions, with sperm function in co-culture such as attachment to OEC and subsequent survival time. Stallions were grouped by cumulative FSC rates observed over three seasons as having average (44 +/- 3%) or high (65 +/- 2%) fertility over a total of 217 first services (31 +/- 9 per stallion). Samples from stallions in the high fertility group had more (P = 0.04) sperm attached to OEC and longer subsequent sperm survival in co-culture (P = 0.05) as compared with those from the average fertility group. FSC rates correlated with numbers of sperm attaching to OEC and their survival time in co-culture (r > or = 0.71). In Experiment 2, the function of cryopreserved stallion sperm was evaluated in culture with OEC secretory products from three different sources. After 5 h of culture, sperm incubated with medium conditioned by bovine OEC which had been 'bioactivated' (e.g. previously exposed to sperm in culture) were found to be more (P < or = 0.05) motile and capacitated as compared to sperm in basal TALP medium alone. Sperm in this conditioned medium also survived longer (P = 0.05; 27 +/- 5 h vs. 17 +/- 4 h) than did those in control medium.
母马体内精子储存库的形成被认为是通过凝集素介导的精子与输卵管上皮的附着来实现的。一旦附着,输卵管因子会支持受精前精子的存活。种马精子的冷冻保存会减少附着在输卵管上皮细胞(OEC)上的精子数量以及这些精子的存活时间。在共培养系统中对精子与OEC之间的体外相互作用进行定量分析,可能会为冷冻保存或新鲜精子样本的功能完整性提供一种检测方法。此外,可以从OEC分泌产物中分离出用于种马精子体外处理的优质添加剂。实验1比较了使用7匹种马的冷冻保存精子后的首次配种受孕(FSC)率,以及精子在共培养中的功能,如与OEC的附着和随后的存活时间。根据在三个季节中观察到的累积FSC率,将种马分为平均生育力(44±3%)或高生育力(65±2%)两组,总共进行了217次首次配种(每匹种马31±9次)。与平均生育力组相比,高生育力组种马的样本中有更多(P = 0.04)的精子附着在OEC上,并且在共培养中精子的后续存活时间更长(P = 0.05)。FSC率与附着在OEC上的精子数量及其在共培养中的存活时间相关(r≥0.71)。在实验2中,用来自三种不同来源的OEC分泌产物在培养中评估冷冻保存的种马精子的功能。培养5小时后,发现与仅在基础TALP培养基中的精子相比,与经“生物活化”(例如先前在培养中接触过精子)的牛OEC条件培养基孵育的精子更具活力且获能程度更高(P≤0.05)。在这种条件培养基中的精子也比对照培养基中的精子存活时间更长(P = 0.05;27±5小时对17±4小时)。