DEVELOPMENT OF AN EMBRYO CRYOPRESERVATION PROGRAM IN LABORATORY ANIMALS

该计划的目标是促进NIH的管理 动物遗传资源（NlHAGR）通过开发和 利用收集、培养、冷冻等技术 移植胚胎和配子进行基因库冷冻 材料和提高生殖潜力。 NlHAGR 维持着许多重要物种，在物种内部， 许多宝贵的基因型用于生物医学研究。 胚胎 保存在冷冻介质中使用冷冻保护剂， 允许足够的脱水以保护卵裂球， 冻死了 解冻和稀释冷冻保护剂后， 培养胚胎以评估体外发育。 胚胎移植到受体雌性体内监测 发展和生物能力。 体外受精 卵子冷冻技术正在被研究， 有限的遗传物质，从单一的女性或菌株与穷人 体内受精率。 库存胚胎保存在 冻结状态，直到需要重新派生。 的主要焦点 实验室的努力是研究和优化冷冻库 技术在小鼠和最近，在兔子。 一个主要的研究 发现胚胎的冷冻性受到混淆和影响， 小鼠的基因型。 这些反应已在 超过55种基因型，其中大多数显示基因型特异性存活 标准化胚胎冻融程序的比率。 辅助 项目是面向比较方面的改善， 长期胚胎储存，特别强调研究 用于胚胎冷冻，解冻， 稀释和转移。 在兔子的努力集中在改进 在收集程序和保存胚胎使用新的 开发了玻璃化冷冻程序。

The program objective is to facilitate the management of the NlH Animal Genetic Resource (NlHAGR) through development and utilization of techniques such as collection, culture, freezing and transfer of embryos and gametes for cryobanking genetic material and improving reproductive potential. The NlHAGR maintains a number of critical species and, within species, vast number of invaluable genotypes used in biomedical research. Embryo preservation uses a cryoprotectant in the freezing medium which allows sufficient dehydration to protect the blastomere during freezing. Following thawing and dilution of the cryoprotectant, embryos are cultured to assess in vitro development. Transplantation of embryos into recipient females monitors in vivo development and thus biological competence. In vitro fertilization and ova freezing are being examined as techniques to salvage limited genetic material from single females or strains with poor in vivo fertilization rates. Banked embryos are maintained in a frozen state until needed for rederivation. A primary focus of laboratory efforts is the study and optimization of cryobanking technology in mice and more recently, in rabbits. A major research finding is that embryo freezability is confounded and influenced markedly by mouse genotype. Such responses have been examined in over 55 genotypes, most of which display genotype specific survival rates to standardized embryo freeze thawing procedures. Ancillary projects are oriented toward the comparative aspects of improving long-term embryo storage with particular emphasis on the study of cryoprotectants and enhancing methods for embryo freezing, thawing, dilution and transfer. Efforts in the rabbit focus on improvements in collection procedures and preservation of embryos using a newly developed vitrification procedure.