Curry M R, Redding B J, Watson P F
Department of Veterinary Basic Sciences, Royal Veterinary College, London, United Kingdom.
Cryobiology. 1995 Apr;32(2):175-81. doi: 10.1006/cryo.1995.1016.
Critical tonicity (tonicity at which 50% of cells swell beyond their maximum volume-to-surface area ratio and lyse) of rabbit spermatozoa was measured as 45.6 mOsm at 22 degrees C. To determine the temperature effect on critical tonicity, cells were equilibrated to 15, 25, and 35 degrees C and critical tonicity was measured as 52.9, 42.2, and 32.4 mOsm, respectively. The time taken for rabbit sperm to achieve lysis at these temperatures was measured by exposing cells for increasing times to distilled water. From these results values for the permeability coefficient of rabbit spermatozoa to water (Lp) and its activation energy (Ea) were calculated. At 25 degrees C, Lp was 0.63 micron/min/atm and was clearly temperature dependent; Ea was 17.8 kcal/mol. Rabbit spermatozoa appear to have a low Lp and high Ea, the opposite of the situation seen with spermatozoa from all other species examined to date which have high Lp and low Ea. Nevertheless, the values obtained permit modeling of cooling rates for cell survival during cryopreservation in keeping with cooling rates commonly employed.
在22摄氏度下，测得兔精子的临界张力（50%的细胞肿胀超过其最大体积与表面积之比并裂解时的张力）为45.6毫渗量。为了确定温度对临界张力的影响，将细胞分别平衡至15、25和35摄氏度，测得的临界张力分别为52.9、42.2和32.4毫渗量。通过将细胞暴露于蒸馏水中的时间逐渐增加，来测量兔精子在这些温度下达到裂解所需的时间。根据这些结果，计算出兔精子对水的渗透系数（Lp）及其活化能（Ea）。在25摄氏度时，Lp为0.63微米/分钟/大气压，且明显依赖于温度；Ea为17.8千卡/摩尔。兔精子似乎具有较低的Lp和较高的Ea，这与迄今为止所研究的所有其他物种的精子情况相反，那些精子具有较高的Lp和较低的Ea。然而，所获得的值允许对冷冻保存期间细胞存活的冷却速率进行建模，这与常用的冷却速率一致。
