Esaian A M, Kucher A G, Kaiukov I G, Ermakov Iu A, Nikogosian Iu A, Riabov S I
Ter Arkh. 2002;74(6):19-24.
To study changes in renal function in response to protein loads in patients with chronic glomerulonephritis (CGN) who have normal renal function and initial uremia.
63 CGN patients were divided into two groups: 40 patients of group 1 (17 males, 23 females, age 16-53 years, plasma creatinine-Pcr < 0.132 mmol/l); 23 patients of group 2 (10 males, 13 females, age 18-57 years, Pcr > 0.132 mmol/l). Renal functional reserve (RFR) was assessed with oral soa isolate SUPRO 760 test (protein Techn. Int., USA), 1.0 g of protein per 1 kg of ideal body mass. By three 2-h clearance periods measurements were made of RFR, absolute and fractional excretion, concentration indices and clearances of creatinine, urea, electrolytes, osmolality. All the parameters were referred to the standard body surface.
RFR was intact in 14 patients of group 1 and 10 patients of group 2. In CGN without uremia with intact RFR, maximal Pcr corresponded to the highest values of minute diuresis and sharp increase of urea excretion, osmotically active substances. In CGN patients with uremia and intact RFR, development of hyperfiltration was accompanied with a significant rise in Pcr, minute diuresis, absolute excretion of urea and osmotically active substances. The rise in the latter two was much less active in CGN if RFR was absent. Multiple stepwise regression analysis showed that RFR intactness depends primarily on baseline values of absolute excretion of urea and osmotically active substances.
A reverse relationship exists between absolute excretion of urea, osmotically active substances and the degree of SKF in response to protein load in CGN patients both in intact nitrogen-excreting function and uremia. It is suggested that urea may be involved in regulation of intraglomerular hemodynamics by means of effect on tubular-glomerular feedback mechanism.
研究肾功能正常及初期尿毒症的慢性肾小球肾炎(CGN)患者对蛋白质负荷的肾功能变化。
63例CGN患者分为两组:第1组40例(男17例,女23例,年龄16 - 53岁,血浆肌酐 - Pcr < 0.132 mmol/l);第2组23例(男10例,女13例,年龄18 - 57岁,Pcr > 0.132 mmol/l)。采用口服大豆分离蛋白SUPRO 760试验(美国Protein Techn. Int.公司)评估肾功能储备(RFR),每1千克理想体重摄入1.0克蛋白质。通过三个2小时清除期测量RFR、绝对排泄率和分数排泄率、浓缩指数以及肌酐、尿素、电解质的清除率、渗透压。所有参数均参照标准体表面积。
第1组14例患者和第2组10例患者的RFR正常。在RFR正常的无尿毒症CGN患者中,最大Pcr对应于最高的每分钟尿量值以及尿素排泄、渗透活性物质的急剧增加。在RFR正常的尿毒症CGN患者中,超滤的发展伴随着Pcr、每分钟尿量、尿素绝对排泄量和渗透活性物质的显著升高。如果RFR不存在,后两者在CGN中的升高则不太明显。多元逐步回归分析表明,RFR的正常与否主要取决于尿素和渗透活性物质的绝对排泄量的基线值。
在CGN患者中,无论是氮排泄功能正常还是处于尿毒症状态,尿素和渗透活性物质的绝对排泄量与对蛋白质负荷的SKF程度之间存在反向关系。提示尿素可能通过影响肾小管 - 肾小球反馈机制参与肾小球内血流动力学的调节。