Cryopreservation and Transport of Mouse Spermatozoa at -79.DEG.C..

Abstract

Abstract:In the present study, 2 experiments were carried out. In experiment 1, mouse spermatozoa were frozen and stored in an ultra-low temperature freezer maintained at -79°C, from 1 week to 8 months. In vitro fertilization rates of the frozen-thawed sperm after 1 week and 4 months of storage were high at 71 and 71%, respectively. These values did not differ significantly from the value (73%) of the control stored at -196°C. In contrast, the 8-month storage rate was significantly lower at 51%. In experiment 2, frozen spermatozoa were transported in a Styrofoam box packed in dry ice from Hokkaido to Tokyo. In vitro fertilization rate of frozen-thawed sperm after transport at -79°C was high at 88%, which was not significantly different from that (84%) of the transported control at -190°C. After transferring two-cell embryos derived from frozen spermatozoa to recipients, 37-62% of the embryos developed into offspring in both experiments. These results indicate that mouse spermatozoa can survive cryopreservation in an ultra-low temperature freezer (-79°C) for up to 4 months and transport at -79°C. Key words: Cryopreservation, mouse spermatozoa, transport can survive cryopreservation at around -80°C for relatively long periods of time (i.e., temperatures which can be achieved using ultra-low temperature freezers or by packing in dry ice), storage and transport of mouse spermatozoa can be simplified, allowing for more widespread use in biomedical research. In the present study, we examined the fertilizing ability of frozen spermatozoa maintained at -79°C for relatively long periods of time and transported by packing in dry ice.Animals: Animals were purchased from CLEA JA-

Dry ice is a reliable substrate for the distribution of frozen mouse spermatozoa: A multi-centric study

“…With regard to mouse spermatozoa, Okamoto et al reported [38] that outbred or hybrid stocks' spermatozoa could be stored at −79°C up to 4 months before losing fertility or could be successfully transported nationally in dry ice.…”

Isolated total RNA and protein are preserved after thawing for more than twenty-four hours

“…Okamoto et al (10) have found that, during tissue freezing and thawing cycles, both the formation of ice crystals and the osmotic effect contribute to RNA degradation. In another study, it was found that RNA and DNA were stable only up to five hours after the tissue was excised when the tissue was maintained at room temperature (5).…”

Transporting Mouse Embryos and Germplasm as Frozen or Unfrozen Materials

“…These parcels are fully disposable, eliminating the need for the receiving facility to return a dry shipper. It is also a safer laboratory practice, as there is a reduced need to handle LN 2 (Okamoto et al, 2001).…”