Akanji A O, Ng L, Humphreys S
Sheikh Rashid Diabetes Unit, Radcliffe Infirmary, Oxford, UK.
Clin Chim Acta. 1988 Nov;178(1):85-94. doi: 10.1016/0009-8981(88)90272-0.
We measured plasma levels of acetate, glucose, insulin, fatty acids and 'ketone bodies' (KB), during fat infusion and continuous simultaneous infusion of insulin and glucose according to a computerized algorithm to maintain fasting euglycaemia and derive indices of tissue insulin sensitivity (hyperinsulinaemic euglycaemic clamping HEC). (i) Plasma acetate levels (mmol/l) approximately doubled (0.14 +/- (SEM) 0.02 to 0.25 +/- 0.02, p less than 0.01) during INTRALIPID infusion in 7 non-diabetic individuals while total 'ketone bodies' and non-esterified fatty acids (NEFAs) increased 10-fold. (ii) Early in the HEC, plasma acetate levels decreased as did NEFAs in 13 non-diabetic (0.17 +/- 0.01 to 0.12 +/- 0.01, p less than 0.001) and 9 diabetic (0.22 +/- 0.02 to 0.15 +/- 0.01, p less than 0.005) individuals. However while acetate levels later rose to fasting values in the non-diabetics, they remained low in the diabetics. NEFA levels were low throughout the clamp but glucose flux was increased as judged from the glucose infusion even with maintained euglycaemia. The change in acetate values during the second hour of the clamp correlated with neither BMI nor two indices of insulin sensitivity (glucose metabolic clearance rate and steady state glucose infusion rate). These results accord with acetate production from glucose and fat oxidation, via acetyl CoA. The differing metabolism of acetate in the second hour of clamping between diabetics and non-diabetics may reflect altered post-receptor glucose metabolism with the onset of diabetes.
我们根据计算机算法在脂肪输注以及胰岛素和葡萄糖持续同步输注期间测量了血浆中乙酸盐、葡萄糖、胰岛素、脂肪酸和“酮体”（KB）的水平，以维持空腹血糖正常，并得出组织胰岛素敏感性指标（高胰岛素正常血糖钳夹技术，HEC）。（i）在7名非糖尿病个体输注英脱利匹特期间，血浆乙酸盐水平（mmol/L）大约翻倍（从0.14±（标准误）0.02增至0.25±0.02，p<0.01），而总“酮体”和非酯化脂肪酸（NEFAs）增加了10倍。（ii）在高胰岛素正常血糖钳夹技术早期，13名非糖尿病个体（从0.17±0.01降至0.12±0.01，p<0.001）和9名糖尿病个体（从0.22±0.02降至0.15±0.01，p<0.005）的血浆乙酸盐水平以及NEFAs均下降。然而，虽然非糖尿病个体的乙酸盐水平随后升至空腹值，但糖尿病个体的乙酸盐水平仍维持在较低水平。在整个钳夹过程中NEFAs水平较低，但从葡萄糖输注情况判断，即使维持血糖正常，葡萄糖通量仍增加。钳夹第二小时乙酸盐值的变化与BMI以及两个胰岛素敏感性指标（葡萄糖代谢清除率和稳态葡萄糖输注率）均无相关性。这些结果与通过乙酰辅酶A由葡萄糖和脂肪氧化生成乙酸盐一致。糖尿病个体和非糖尿病个体在钳夹第二小时乙酸盐代谢的差异可能反映了糖尿病发病后受体后葡萄糖代谢的改变。
