Shabana M, McGrath J J
Mechanical Engineering Department, Michigan State University, East Lansing 48824.
Cryobiology. 1988 Aug;25(4):338-54. doi: 10.1016/0011-2240(88)90042-9.
Thermodynamic computer modeling was used to predict the freezing response of single-celled unfertilized hamster ova. The cell membrane transport characteristics were investigated, using a microscope diffusion chamber system. The mean osmotically inactive cell volume was determined to be 21.6% of the initial cell volume. An overall mean value of 0.8 +/- 0.1 micron3/micron2.min.atm (= 18 +/- 2.5 micron/sec) was determined for the membrane hydraulic coefficient, Lp. The effect of the extracellular solute concentration on Lp was determined at room temperature (approximately 23 degrees C). A thermodynamic computer model was used to predict the cell response to freezing. The predicted response was compared to the actual volumetric response observed during freezing on a temperature-controlled cryomicroscope conduction stage. The effect of the cooling rate on the nucleation temperature of unprotected ova and protected ova suspended in a 1.5 M DMSO solution was investigated. Overall mean nucleation temperatures of -13 and -57.1 degrees C were observed for unprotected and protected ova, respectively, where the mean nucleation temperature for protected ova was strongly cooling rate dependent.
利用热力学计算机建模来预测单细胞未受精仓鼠卵的冷冻反应。使用显微镜扩散室系统研究细胞膜转运特性。确定平均非渗透活性细胞体积为初始细胞体积的21.6%。测定膜水力系数Lp的总体平均值为0.8±0.1立方微米/平方微米·分钟·大气压（=18±2.5微米/秒）。在室温（约23摄氏度）下测定细胞外溶质浓度对Lp的影响。使用热力学计算机模型预测细胞对冷冻的反应。将预测反应与在温度控制的低温显微镜传导台上冷冻期间观察到的实际体积反应进行比较。研究了冷却速率对悬浮在1.5M二甲基亚砜溶液中的未保护卵和受保护卵的成核温度的影响。未保护卵和受保护卵的总体平均成核温度分别为-13摄氏度和-57.1摄氏度，其中受保护卵的平均成核温度强烈依赖于冷却速率。
