Orita H, Fukasawa M, Hirooka S, Uchino H, Fukui K, Kohi M, Washio M
Second Department of Surgery, Yamagata University School of Medicine, Japan.
Ann Thorac Surg. 1994 Oct;58(4):1103-7. doi: 10.1016/0003-4975(94)90466-9.
The purpose of the present study was to evaluate the functional and biochemical effects of glucose-based solutions in combination with potassium or insulin (or both) on immature myocytes under hypothermic conditions. Myocytes were isolated from neonatal rat ventricles and cultured for 4 days with MCDB 107 (University of Colorado solution). Initially, myocytes (12.5 x 10(5) myocytes/flask) were incubated at 4 degrees C for 6 hours in 5% glucose solution containing various potassium concentrations ranging from 0 to 80 mEq/L to evaluate the protective effects. Next, myocytes were incubated at 4 degrees C for 3, 6, 12, 18, and 24 hours in three types of solutions: normal saline solution (control), glucose-potassium solution, and glucose-insulin-potassium solution (glucose: 50 g/L; NaHCO3, 20 mEq; potassium, 20 mEq; insulin, 20 IU/L). After each incubation, creatine kinase and lactate dehydrogenase levels were measured in the incubation solutions. The myocytes then were cultured for an additional 24 hours at 37 degrees C to evaluate the recovery of myocyte beating rate. The 20-mEq potassium treatment showed significantly better beating rate recovery and lower enzymal release than the glucose-only control. The saline solution showed the best protection of all three solutions, both functionally and biochemically, by 12 hours. The greatest damage was observed with glucose-potassium solution, beginning at 3 hours of hypothermic incubation. Although potassium and insulin have additional protective effects on hypothermic preservation, the high concentration of glucose has noxious characteristics for immature myocytes that may not be suitable for cardiac preservation in the neonatal period.
本研究的目的是评估基于葡萄糖的溶液与钾或胰岛素（或两者）联合使用对低温条件下未成熟心肌细胞的功能和生化影响。从新生大鼠心室分离心肌细胞，并用MCDB 107（科罗拉多大学溶液）培养4天。最初，将心肌细胞（12.5×10⁵个心肌细胞/培养瓶）在含有0至80 mEq/L不同钾浓度的5%葡萄糖溶液中于4℃孵育6小时，以评估保护作用。接下来，将心肌细胞在三种溶液中于4℃孵育3、6、12、18和24小时：生理盐水溶液（对照）、葡萄糖 - 钾溶液和葡萄糖 - 胰岛素 - 钾溶液（葡萄糖：50 g/L；NaHCO₃，20 mEq；钾，20 mEq；胰岛素，20 IU/L）。每次孵育后，测量孵育溶液中的肌酸激酶和乳酸脱氢酶水平。然后将心肌细胞在37℃再培养24小时，以评估心肌细胞搏动率的恢复情况。与仅用葡萄糖的对照组相比，20 mEq钾处理显示出明显更好的搏动率恢复和更低的酶释放。在功能和生化方面，生理盐水溶液在12小时时对所有三种溶液显示出最佳保护作用。从低温孵育3小时开始，葡萄糖 - 钾溶液观察到最大损伤。尽管钾和胰岛素对低温保存有额外的保护作用，但高浓度葡萄糖对未成熟心肌细胞具有有害特性，可能不适用于新生儿期的心脏保存。
