OBJECTIVE To determine whether the daily pattern of urine excretion of N wastes is affected by obesity and very low-calorie diets (VLCD). DESIGN The plasma amino acid, urea and other energy parameters, as well as the urinary excretion of total nitrogen, urea and creatinine were studied in obese and normal-weight women. The obese women's data were obtained under hospital basal controlled conditions (8.1 MJ/day) and after 3 days of VLCD diet (1.9 MJ/day) controls were studied only once (5.8 MJ/day). The hourly excretion patterns of total N, urea and creatinine were determined from the composition of each bladder voiding. SUBJECTS Twenty morbidly obese and 10 age-matched normal-weight control women. RESULTS Plasma amino acid levels were higher in obese women, which showed a limited ability to metabolize amino acid hydrocarbon skeletons. Neither differences in the patterns between groups nor total 24 h values for urine volume were found. Total N and urea excretion diminished under VLCD diet. Hourly creatinine excretion showed a flat pattern and was higher in obese women than in the controls, VLCD diet diminished the amount of creatinine excreted in 24 h. CONCLUSIONS The early change in energy availability that the creatinine excretion figures reflect may result from the energy conservation mechanisms induced in response to energy restriction. The early onset of this effect (3 days, and the extent of decrease (approximately 19%) also suggest that the impact of VLCD on the muscle energy budget of the obese is more marked than usually assumed.

中文翻译：

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低热量饮食对病态肥胖妇女氮排泄的短期影响。

目的确定肥胖和低热量饮食（VLCD）是否会影响N废物尿液的每日排泄方式。设计在肥胖和体重正常的女性中研究了血浆氨基酸，尿素和其他能量参数，以及总氮，尿素和肌酐的尿排泄量。肥胖妇女的数据是在医院基本控制的条件下（8.1 MJ /天）获得的，VLCD饮食3天（1.9 MJ /天）后仅对对照者进行了一次研究（5.8 MJ /天）。从每个膀胱排泄物的组成确定总氮，尿素和肌酐的每小时排泄方式。受试者：20名病态肥胖和10名年龄匹配的正常体重控制妇女。结果肥胖女性的血浆氨基酸水平较高，这表明其代谢氨基酸碳氢化合物骨架的能力有限。两组之间的模式差异和总尿量的24小时值均未发现。在VLCD饮食下，总氮和尿素排泄量减少了。肥胖妇女每小时的肌酐​​排泄量呈扁平状，高于对照组，VLCD饮食减少了24小时内肌酐的排泄量。结论肌酸酐排泄量所反映的能量可及性的早期变化可能是由于响应能量限制而诱导的能量守恒机制造成的。这种效应的早期发作（3天，下降的幅度（约19％））也表明，VLCD对肥胖者肌肉能量收支的影响比通常的设想更为明显。在VLCD饮食下，总氮和尿素排泄量减少了。肥胖妇女每小时的肌酐​​排泄量呈扁平状，高于对照组，VLCD饮食减少了24小时内肌酐的排泄量。结论肌酸酐排泄量所反映的能量可及性的早期变化可能是由于响应能量限制而诱导的能量守恒机制造成的。这种效应的早期发作（3天，下降的幅度（约19％））也表明，VLCD对肥胖者肌肉能量收支的影响比通常的设想更为明显。在VLCD饮食下，总氮和尿素排泄量减少了。肥胖妇女每小时的肌酐​​排泄量呈扁平状，高于对照组，VLCD饮食减少了24小时内肌酐的排泄量。结论肌酸酐排泄量所反映的能量可及性的早期变化可能是由于响应能量限制而诱导的能量守恒机制造成的。这种效应的早期发作（3天，下降的幅度（约19％））也表明，VLCD对肥胖者肌肉能量收支的影响比通常的设想更为明显。结论肌酸酐排泄量所反映的能量可及性的早期变化可能是由于响应能量限制而诱导的能量守恒机制造成的。这种效应的早期发作（3天，下降的幅度（约19％））也表明，VLCD对肥胖者肌肉能量收支的影响比通常的设想更为明显。结论肌酸酐排泄量所反映的能量可及性的早期变化可能是由于响应能量限制而诱导的能量守恒机制造成的。这种效应的早期发作（3天，下降的幅度（约19％））也表明，VLCD对肥胖者肌肉能量收支的影响比通常的设想更为明显。