Owen P, du Toit E F, Opie L H
Department of Medicine, Groote Schuur Hospital, Cape Town, South Africa.
J Thorac Cardiovasc Surg. 1993 Jun;105(6):995-1006.
The purpose of this study was to determine the mechanisms by which high physiologic concentrations of glucose (11 mmol/L) were protective while even higher concentrations (20 or 50 mmol/L) were harmful when added to St. Thomas' Hospital No. 2 cardioplegic solution. We evaluated the recovery of isolated working rat hearts subjected to 3 hours of hypothermic multidose cardioplegic arrest. The addition of glucose 11 mmol/L was associated with better aortic flow (79.2% +/- 1.3%) than the addition of glucose 1 mmol/L (61.7% +/- 2.7%), 20 mmol/L (73.6% +/- 1.1%), or 50 mmol/L (66.0% +/- 3.2%) (p < 0.01 versus glucose 1 and 50 mmol/L). An increase in glucose concentration from 1 to 50 mmol/L progressively augmented glucose flux from 2.2 +/- 0.33 to 10.4 +/- 0.79 mumol/gm per 3 hours (p < 0.01), but higher glucose concentrations of 20 and 50 mmol/L inhibited glycogenolysis (p < 0.05 versus glucose 1 and 11 mmol/L), so that total glycolysis was decreased and consequently glycolytic adenosine triphosphate production was reduced from 35.9 +/- 0.47 (glucose 11 mmol/L) to 27.5 +/- 1.25 mumol/gm per 3 hours (glucose 50 mmol/L) (p < 0.01). The end products of glycolysis (lactate and protons) did not appear to affect the recovery of the hearts, because both lactate efflux and tissue lactate were highest in the presence of glucose 11 mmol/L and the pH of the cardioplegic effluent was more alkalotic in glucose 11 and 20 mmol/L. Thus a high physiologic concentration of glucose (11 mmol/L) in the cardioplegic solution improved recovery because of an increased glycolytic adenosine triphosphate production during cardioplegic arrest, whereas even higher concentrations of glucose inhibited these effects.
本研究的目的是确定高生理浓度葡萄糖（11 mmol/L）具有保护作用，而当添加到圣托马斯医院2号心脏停搏液中时，更高浓度（20或50 mmol/L）却具有有害作用的机制。我们评估了接受3小时低温多剂量心脏停搏的离体工作大鼠心脏的恢复情况。添加11 mmol/L葡萄糖时的主动脉血流量（79.2%±1.3%）比添加1 mmol/L葡萄糖（61.7%±2.7%）、20 mmol/L葡萄糖（73.6%±1.1%）或50 mmol/L葡萄糖（66.0%±3.2%）时更好（与1和50 mmol/L葡萄糖相比，p<0.01）。葡萄糖浓度从1 mmol/L增加到50 mmol/L时，葡萄糖通量从每3小时2.2±0.33 μmol/g逐渐增加到10.4±0.79 μmol/g（p<0.01），但20和50 mmol/L的较高葡萄糖浓度抑制了糖原分解（与1和11 mmol/L葡萄糖相比，p<0.05），从而使总糖酵解减少，因此糖酵解产生的三磷酸腺苷从每3小时35.9±0.47 μmol/g（11 mmol/L葡萄糖）降至27.5±1.25 μmol/g（50 mmol/L葡萄糖）（p<0.01）。糖酵解终产物（乳酸和质子）似乎并未影响心脏的恢复，因为在11 mmol/L葡萄糖存在时，乳酸流出和组织乳酸含量均最高，且在11和20 mmol/L葡萄糖的心脏停搏液流出液中pH值更偏碱性。因此，心脏停搏液中高生理浓度的葡萄糖（11 mmol/L）可改善恢复情况，这是因为在心脏停搏期间糖酵解产生的三磷酸腺苷增加，而更高浓度的葡萄糖则抑制了这些作用。
