Vreugdenhil P K, Belzer F O, Southard J H
Department of Surgery, University of Wisconsin, Madison 53792.
Cryobiology. 1991 Apr;28(2):143-9. doi: 10.1016/0011-2240(91)90016-h.
One of the mechanisms thought to cause injury in preserved organs is the formation of oxygen free radicals. The cell is protected from oxidative stress by many defense mechanisms. A major defense mechanism involves glutathione and glutathione-dependent enzymes. During organ preservation by simple cold storage the loss of glutathione may sensitize the organ to free radical damage after transplantation. In this study we show that glutathione is depleted from the rabbit liver, kidney, and heart cold-stored (5 degrees C) for up to 72 h in the UW solution without glutathione. In the first 24 h kidney glutathione decreased to 84 +/- 3% of control values, liver glutathione decreased to 49 +/- 3% of control values, and heart glutathione decreased to 73 +/- 3% of control values. After 48 h of storage the kidney and liver lost an additional 30 and 20%, respectively, whereas heart glutathione changed very little. By 72 h all three organs had lost more than 50% of the glutathione found in freshly obtained tissue. To determine if glutathione added to the UW solution can effectively prevent this loss of glutathione during preservation, hepatocytes were cold-stored for up to 72 h in a preservation solution with and without glutathione. We found that adding glutathione to the preservation solution slowed the rate of loss of glutathione from the cells. These data suggest that at hypothermia the cell may be permeable to GSH. Methods to suppress the loss of glutathione during preservation of organs may be an important factor in suppressing oxygen free radical injury.
一种被认为会导致保存器官损伤的机制是氧自由基的形成。细胞通过多种防御机制来抵御氧化应激。一种主要的防御机制涉及谷胱甘肽和依赖谷胱甘肽的酶。在通过简单冷藏保存器官的过程中,谷胱甘肽的流失可能会使器官在移植后对自由基损伤更加敏感。在本研究中,我们发现,在不含谷胱甘肽的UW溶液中,兔的肝脏、肾脏和心脏在5℃冷藏长达72小时后,谷胱甘肽会减少。在最初的24小时内,肾脏中的谷胱甘肽降至对照值的84±3%,肝脏中的谷胱甘肽降至对照值的49±3%,心脏中的谷胱甘肽降至对照值的73±3%。储存48小时后,肾脏和肝脏分别又损失了30%和20%,而心脏中的谷胱甘肽变化很小。到72小时时,所有三个器官中谷胱甘肽的损失都超过了新鲜组织中谷胱甘肽含量的50%。为了确定添加到UW溶液中的谷胱甘肽是否能有效防止保存过程中谷胱甘肽的这种流失,将肝细胞在含有和不含谷胱甘肽的保存溶液中冷藏长达72小时。我们发现,在保存溶液中添加谷胱甘肽减缓了细胞内谷胱甘肽的流失速度。这些数据表明,在低温下细胞可能对谷胱甘肽具有通透性。抑制器官保存过程中谷胱甘肽流失的方法可能是抑制氧自由基损伤的一个重要因素。