Christopher M M, Eckfeldt J H, Eaton J W
Department of Veterinary Pathobiology, University of Minnesota, St. Paul.
Lab Invest. 1990 Jan;62(1):114-8.
Propylene glycol (1,2-propanediol) is a solvent in numerous pharmaceuticals and a major preservative and source of carbohydrates in processed foods. In mammals, propylene glycol is metabolized similar to ethanol, proceeding via hepatic alcohol and aldehyde dehydrogenases to lactate, which can then enter gluconeogenesis. We observed that cats ingesting 1.6 gm of propylene glycol/kg body weight/day developed increased anion gap. To investigate this further, we measured D- and L-lactate concentrations in these cats; we also measured D-lactate in cats ingesting high doses of propylene glycol (8.0 gm/kg). While L-lactate actually decreased throughout the 35-day course of propylene glycol feeding, D-lactate levels were significantly increased on a dose-dependent basis and correlated positively with anion gap. In cats ingesting the high dose of propylene glycol, D-lactate concentrations were as high as 7 mmol/liter, levels associated with encephalopathy in humans. Indeed, this group of cats developed depression and ataxia, consistent with intoxication by D-lactate. These findings are significant not only for animals ingesting diets which contain propylene glycol, but for humans who receive propylene glycol-containing medications.
丙二醇（1,2 - 丙二醇）是众多药物中的一种溶剂，也是加工食品中的主要防腐剂和碳水化合物来源。在哺乳动物体内，丙二醇的代谢过程与乙醇相似，通过肝脏中的醇脱氢酶和醛脱氢酶代谢为乳酸，然后乳酸可进入糖异生过程。我们观察到，猫每天每千克体重摄入1.6克丙二醇时，阴离子间隙会增加。为了进一步研究这一现象，我们测量了这些猫体内D - 乳酸和L - 乳酸的浓度；我们还测量了摄入高剂量丙二醇（8.0克/千克）的猫体内的D - 乳酸浓度。在整个35天的丙二醇喂食过程中，L - 乳酸实际上有所下降，而D - 乳酸水平则呈剂量依赖性显著升高，并与阴离子间隙呈正相关。在摄入高剂量丙二醇的猫中，D - 乳酸浓度高达7毫摩尔/升，这一水平与人类脑病有关。实际上，这群猫出现了抑郁和共济失调，这与D - 乳酸中毒相符。这些发现不仅对摄入含丙二醇饮食的动物具有重要意义，对接受含丙二醇药物治疗的人类也具有重要意义。
