基因组学与应用生物学

本研究探讨了玻璃化冷冻保存对牛体外受精胚胎冻后存活的影响。7日龄的胚胎在10%甘油+20%丙二醇的玻璃化冷冻液中,室温下停留10 min,其孵化率为86.6%,与对照的83.2%相比,无明显影响(P>0.05)。然10%甘油+20%乙二醇,25%甘油+25%乙二醇及25%甘油+25%丙二醇均明显降低胚胎的孵化率(P<0.01)。7日龄胚胎经10%甘油及10%甘油+20%乙二醇依次平衡5 min后,再置于25%甘油+25%乙二醇的冷冻液中,20 s内投液氮玻璃化冷冻,冻后孵化率达80.8%,明显高于其它平衡方法。冷冻液为25%甘油+25%乙二醇的胚胎冻后总孵化率为72.1%,明显高于25%甘油+25%丙二醇的60.9%。这些结果表明:牛胚胎玻璃化冷冻保存的成功率在很大程度上取决于防冻剂的种类、浓度及平衡方法。

In Exp.1,the toxicity of 4 vitrification solutions were tested on Day 7-8 bovine blastocysts produced in vitro.The solution of 10% glycerol(G)+20% propylene glycol(PG)was not toxic to embryos,the hatching rate(83.2%)of the embryos exposed to this solution was comparable to that(86.6%)of the controls(P>0.05).Exposure of embryos to 10% G+20% ethylene glycol(EG)significantly reduced the hatching rate (66.7%,P<0.01)while exposure to 25%G+25% EG and 25%G+25% PG nearly killed all the embryos(hatching rate:4.9% and 0 resp.,P<0.01). In Exp.2,Day 7 blastocysts were vitrified after being exposed to the vitrification solutions at room temperature using different equilibration procedures.When G+EG was used,embryos exposed first to 10% G showed significantly higher hatching rate than those exposed first to 20%EG(80.8% vs 60.4%,P<0.01),while those directly equilibrated in 10%G+20% EG gave an intermediate hatching rate(75.0%),which was not significantly different from that of the above 2 groups(P>0.05).WhenG+PG was used,the hatching rate(73.6%)of the embryos equilibrated first in 20% PG was significantly higher than that (51.1%)of the embryos exposed first to 10%G(P<0.01),the hatching rate(58.8%)of embryos exposed directly to 10%G+20%PG was not significantly different from that of the other 2 groups(P>0.05).