Stenvinkel P, Alvestrand A
Karolinska Institute, Department of Renal Medicine, Huddinge University Hospital, Stockholm, Sweden.
Nephrol Dial Transplant. 1994;9(12):1728-33.
The effect of physiological hyperinsulinaemia on renal haemodynamics and renal sodium handling was studied in nine healthy males on two separate study occasions with and without indomethacin pretreatment, using the euglycaemic insulin clamp technique. Renal haemodynamics and segmental tubular sodium handling were evaluated by determining the inulin, PAH, sodium and lithium clearances. Changes in urinary dopamine excretion were also studied. Insulin infusion caused similar increases in renal plasma flow with as well as without indomethacin pretreatment, but no change in glomerular filtration rate in both experimental settings. Following indomethacin pretreatment, the basal sodium clearance decreased from 1.6 +/- 0.2 to 0.8 +/- 0.2 ml/min and the basal urinary dopamine excretion decreased from 107 +/- 8 to 86 +/- 6 nmol/h. In conclusion, the present study demonstrates a direct renal vasodilatory effect of insulin in healthy subjects that does not seem to be dependent on renal prostaglandins. Moreover, under the present experimental circumstances indomethacin reduced the basal urinary dopamine output, which could reflect a reduction in the filtered load of sodium following indomethacin pretreatment.
采用正常血糖胰岛素钳夹技术，在9名健康男性身上进行了两项独立的研究，分别在有和没有吲哚美辛预处理的情况下，研究生理性高胰岛素血症对肾血流动力学和肾钠处理的影响。通过测定菊粉、对氨基马尿酸、钠和锂清除率来评估肾血流动力学和节段性肾小管钠处理。还研究了尿多巴胺排泄的变化。无论有无吲哚美辛预处理，胰岛素输注都会使肾血浆流量出现类似的增加，但在两种实验设置下肾小球滤过率均无变化。吲哚美辛预处理后，基础钠清除率从1.6±0.2降至0.8±0.2 ml/分钟，基础尿多巴胺排泄量从107±8降至86±6 nmol/小时。总之，本研究表明胰岛素对健康受试者有直接的肾血管舒张作用，这似乎不依赖于肾前列腺素。此外，在本实验条件下，吲哚美辛降低了基础尿多巴胺输出，这可能反映了吲哚美辛预处理后钠滤过负荷的降低。
