Establishment of cryo-preservation method for ovary and testis and storage of wild mouse genes.

本研究旨在从保存基因资源的角度出发，通过冷冻卵巢和睾丸建立野生小鼠基因组保存体系。建立了卵巢和野生鼠基因的冷冻保存方法。通过一系列的实验，确定了成功的卵巢冷冻条件。将自由法应用于日本野鼠来源的MSM近交系的卵巢，获得了来自冷冻卵巢的小鼠，尽管小鼠的产仔数很小。睾丸冷冻保存方法的建立新生小鼠睾丸冷冻损伤的组织学观察。将冷冻的新生睾丸移植到组织相容的成人睾丸内，在TIL-40ﾟC缓慢降温的程序中，许多生殖细胞在浸入LN前保持了正常的形态。在上述冷冻方案的情况下，在移植后14天观察到减数分裂生殖细胞，并在6周时在来自冷冻睾丸的生精小管中检测到精子，尽管尚未证实它们是否具有受精卵母细胞的能力。解冻的睾丸向宿主生殖系统的重建正在调查中。

This study aimed at an establishment of storage system for wild mouse genome by freezing of ovary and testis from a viewpoint of preservation of gene resources.1. Establishment of cryo-preservation method for ovary and strage of wild mouse genes.Successful freezing conditions of ovaries were detected in a series of experiments using laboratory mice. When the freesing method was applied to ovaries of MSM inbred strain derived from Japanese wild mice, mice derived from frozen ovaries were obtained, though litter sizes were very small.2. Establishment of cryo-preservation method for testisfreezing injuries of newborn mouse testes were examined histologically at various points of a freezing course. A lot of germ cells retained a normal morphology in the program of slow cooling til -40ﾟC before immersion into LN2.In order to confirm the growth of germ cells and the production of spermatozoa, the frozen newborn testis were transplanted into histocompatible adult testis. In the case of a freezing program described above, at 14 days after transplantation meiotic germ cells were observed and at six weeks spermatozoa were detected in the seminiferous tubules derived from the frozen testes, though it has not been confirmed whether they have a capacity of fertilization to oocytes.A reconstitution of thawed testis to a host reproductive system is under investigation.