Skøtt P, Vaag A, Hother-Nielsen O, Andersen P, Bruun N E, Giese J, Beck-Nielsen H, Parving H H
Steno Memorial and Hvidøre Hospital, Klampenborg, Denmark.
Scand J Clin Lab Invest. 1991 Dec;51(8):715-27. doi: 10.3109/00365519109104586.
In normoalbuminuric patients with insulin-dependent diabetes mellitus, plasma atrial natriuretic factor (ANF), cyclic GMP and active renin and the renal clearances of [99Tcm]-diethylenetriaminepentaacetic acid (DTPA) lithium and sodium were studied on a hyperglycaemia day and a euglycaemia day. Baseline euglycaemia was achieved by an overnight variable insulin infusion, which during study days was fixed at the rate necessary to maintain euglycaemia in the morning. After a baseline euglycaemic clearance period of 90 min, measurements were repeated in a new 90-min period beginning 150 min later. On the hyperglycaemia day i.v. infusion of 20% glucose was started at the end of the euglycaemic baseline period, increasing blood glucose (5.3 +/- 1.3 vs 12.1 +/- 1.2 mmol l-1, p less than 0.01). On the euglycaemia day blood glucose declined (5.1 +/- 1.0 vs 4.2 +/- 1.0 mmol l-1, p less than 0.02). Glomerular filtration rate (GFR) was unchanged by acute hyperglycaemia (127 +/- 16 vs 129 +/- 24 ml min-1, NS), but nearly normalized during maintained euglycaemia on the euglycaemia day (124 +/- 17 vs 105 +/- 16 ml min-1, p less than 0.01). When comparing the hyperglycaemic study period with the similarly timed period on the euglycaemia day, GFR was elevated by hyperglycaemia (129 +/- 24 vs 105 +/- 16 ml min-1, p less than 0.01), while the renal clearances of lithium and sodium were similar. Consequently, the calculated absolute proximal reabsorption rate of sodium and water was elevated during hyperglycaemia. Hyperglycaemia reduced the slight decline in plasma concentrations of ANF and cyclic GMP observed on the euglycaemia day. Active renin, glucagon and plasma osmolality were unchanged. In conclusion, marked changes in glomerular filtration rate are induced by changes in blood glucose concentration, but the effect is delayed and thus not directly related to renal tubular transport of glucose. Hyperglycaemia does not affect renal clearances of lithium and sodium, while proximal tubular reabsorption is markedly stimulated. These changes are not related to changes in ANF, renin, glucagon or plasma osmolality.
在胰岛素依赖型糖尿病的正常白蛋白尿患者中，于高血糖日和正常血糖日研究了血浆心钠素（ANF）、环磷酸鸟苷（cGMP）、活性肾素以及[99锝] - 二乙三胺五乙酸（DTPA）锂和钠的肾清除率。通过过夜可变胰岛素输注实现基线正常血糖，在研究日期间将其固定在维持早晨正常血糖所需的速率。在90分钟的基线正常血糖清除期后，在150分钟后开始的新的90分钟期间重复测量。在高血糖日，在正常血糖基线期结束时开始静脉输注20%葡萄糖，血糖升高（5.3±1.3对12.1±1.2 mmol/L，p<0.01）。在正常血糖日，血糖下降（5.1±1.0对4.2±1.0 mmol/L，p<0.02）。急性高血糖未改变肾小球滤过率（GFR）（127±16对129±24 ml/min，无显著性差异），但在正常血糖日维持正常血糖期间GFR几乎恢复正常（124±17对105±16 ml/min，p<0.01）。当将高血糖研究期与正常血糖日相同时间的时期进行比较时，高血糖使GFR升高（129±24对105±16 ml/min，p<0.01），而锂和钠的肾清除率相似。因此，高血糖期间计算出的钠和水的绝对近端重吸收率升高。高血糖减少了在正常血糖日观察到的ANF和cGMP血浆浓度的轻微下降。活性肾素、胰高血糖素和血浆渗透压未改变。总之，血糖浓度的变化可诱导肾小球滤过率发生显著变化，但这种效应具有延迟性，因此与肾小管对葡萄糖的转运无直接关系。高血糖不影响锂和钠的肾清除率，而近端肾小管重吸收受到明显刺激。这些变化与ANF、肾素、胰高血糖素或血浆渗透压的变化无关。
