Wang T, Banker M C, Claydon M, Hicks G L, Layne J R
Department of Surgery, University of Rochester, New York 14642.
Cryobiology. 1992 Aug;29(4):470-7. doi: 10.1016/0011-2240(92)90049-8.
We studied the colligative cryoprotective effect of ethanol (EtOH) in preserving the isolated rat heart frozen at -3.4 degrees C or unfrozen at -1.4 degrees C. Addition of 4.7% (v/v) EtOH to a cardioplegic solution, CP-14, raised the osmolality from 280 to 1100 mOsm/kg H2O and lowered the melting point from -0.52 to -2.1 degrees C. Freezing of the cardiac explant at -3.4 degrees C for 6 h resulted in 34.3 +/- 1.9% of the tissue water as ice; recovery of cardiac output (CO) was 50%. Polyethylene glycol, which at 5% (w/v) has been shown to cryoprotect the hearts during freezing at -1.4 degrees C, did not improve the protective effect of 4.7% EtOH. CP-14 + 4.7% EtOH did not freeze at -1.4 degrees C. After 6 h storage, CO in hearts flushed with CP-14 + 4.7% EtOH oxygenated with 95% O2/5%CO2 returned to almost control level and was much higher than that in hearts flushed with 100% O2 saturated-CP-14 + 4.7% EtOH. Storage of 8 and 12 h reduced CO to 87 +/- 9 and 60 +/- 5% of control. By employing EtOH as a colligative cryoprotectant, we preserved the adult mammalian heart frozen at -3.4 degrees C or unfrozen at -1.4 degrees C, suggesting that this small molecular weight, penetrating substance may be a suitable cryoprotectant for long-term storage of the cardiac explant at high subzero temperatures.
我们研究了乙醇（EtOH）在保存于-3.4℃冷冻或-1.4℃未冷冻的离体大鼠心脏中的依数性冷冻保护作用。向心脏停搏液CP-14中添加4.7%（v/v）的EtOH，使渗透压从280 mOsm/kg H₂O升高至1100 mOsm/kg H₂O，并使熔点从-0.52℃降至-2.1℃。将心脏外植体在-3.4℃冷冻6小时后，组织水分中有34.3±1.9%形成了冰；心输出量（CO）的恢复率为50%。5%（w/v）的聚乙二醇已被证明在-1.4℃冷冻期间可对心脏起到冷冻保护作用，但它并不能增强4.7% EtOH的保护效果。CP-14 + 4.7% EtOH在-1.4℃不会结冰。储存6小时后，用95% O₂/5% CO₂ 氧合的CP-14 + 4.7% EtOH冲洗的心脏中的CO几乎恢复到对照水平，且远高于用100% O₂饱和的CP-14 + 4.7% EtOH冲洗的心脏。储存8小时和12小时后，CO分别降至对照值的87±9%和60±5%。通过将EtOH用作依数性冷冻保护剂，我们成功保存了在-3.4℃冷冻或-1.4℃未冷冻的成年哺乳动物心脏，这表明这种小分子的可渗透物质可能是在零下较高温度下长期保存心脏外植体的合适冷冻保护剂。
