Domínguez M C, Herrera E
Rev Esp Fisiol. 1976 Dec;32(4):293-300.
To study the kinetics of glycerol utilization by adipose tissue in vitro as function of the concentrations of both glycerol and glucose in the incubation media, pieces of epididymal fat pad from fed rats were incubated for different times in Krebs Ringer bicarbonate supplemented with 1-14C-glycerol and purified albumin. An increase in the concentration of glycerol in the medium produces a decrease in the formation of 14CO2 and 14C-lipids from 1-14C-glycerol. When the decrease in the specific activity of the tracer is considered to calculate the respective velocities, it turns out that glycerol actually enhances the rate of synthesis of both CO2 and glyceride glycerol. Glucose enhances the rate of synthesis of CO2 and fatty acids from glycerol but decreases the rate of glyceride glycerol synthesis from the same substrate. While the Km of the glycerol effect is much lower that the physiological concentrations of glycerol the Ka and Ki of the glucose effects are above or close to its concentration in blood. The results are discussed in terms of the competitive effects of glucose and glycerol for the synthesis of alpha-glycerophosphate and the necessity of glucose for lipogenesis from glycerol in adipose tissue.
为了研究体外脂肪组织利用甘油的动力学与孵育培养基中甘油和葡萄糖浓度的关系，将喂食大鼠的附睾脂肪垫切成小块，在补充了1-¹⁴C-甘油和纯化白蛋白的 Krebs-Ringer 碳酸氢盐溶液中孵育不同时间。培养基中甘油浓度的增加会导致¹⁴C-甘油生成¹⁴CO₂和¹⁴C-脂质的量减少。当考虑示踪剂比活性的降低来计算各自的速度时，结果表明甘油实际上提高了CO₂和甘油酯甘油的合成速率。葡萄糖提高了甘油生成CO₂和脂肪酸的速率，但降低了相同底物生成甘油酯甘油的速率。虽然甘油效应的Km远低于甘油的生理浓度，但葡萄糖效应的Ka和Ki高于或接近其血液浓度。根据葡萄糖和甘油对α-磷酸甘油合成的竞争效应以及脂肪组织中甘油生成脂肪所需葡萄糖的必要性对结果进行了讨论。
