Fine B P, Ty A, Lestrange N, Levine O R
Department of Pediatrics, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark 07103-2757.
J Nutr. 1987 Sep;117(9):1623-8. doi: 10.1093/jn/117.9.1623.
Dietary control of sodium intake was utilized in weanling rats to study the relationships among body growth, tissue composition and extracellular fluid volume (ECFV). Forty 3-wk-old rats were divided into groups receiving 30, 150, 300, 600 or 900 mu eq sodium/d for 5 wk. The minimal daily requirement for normal growth was 300 mu eq Na, or about 60 mu eq/g of new growth. Lower doses caused dose-related growth failure associated with a reduced ECFV. Analyses of carcass, muscle and bone composition were carried out. In sodium-deprived animals there was retarded growth of protoplasm, fat and bone; the mineral composition of muscle was not altered, whereas in bone calcium concentration was reduced. Plasma concentrations of sodium, potassium and chloride remained normal. Pair-feeding indicated that sodium-deficiency growth retardation could not be attributed to starvation. Sodium-deficient animals ingested a greater amount of food per gram of weight gain, possibly reflecting an increased energy expenditure. Sodium deprivation initially permitted protoplasmic growth to proceed at a rate disproportionate to that of the ECFV. Subsequently, both continued to grow at a reduced but similar rate, suggesting that ECFV may be a controller of protoplasmic growth.
通过控制断奶大鼠的钠摄入量，研究其身体生长、组织成分与细胞外液量（ECFV）之间的关系。将40只3周龄大鼠分为几组，分别给予每日30、150、300、600或900微当量钠，持续5周。正常生长的每日最低需求量为300微当量钠，即每克新生长组织约60微当量钠。较低剂量会导致与ECFV减少相关的剂量依赖性生长衰竭。对胴体、肌肉和骨骼成分进行了分析。在缺钠动物中，原生质、脂肪和骨骼的生长受到抑制；肌肉的矿物质成分未改变，而骨骼中的钙浓度降低。血浆钠、钾和氯浓度保持正常。配对喂养表明，钠缺乏导致的生长迟缓不能归因于饥饿。缺钠动物每增加一克体重摄入的食物量更多，这可能反映了能量消耗增加。缺钠最初使原生质生长速度与ECFV的生长速度不成比例。随后，两者均以降低但相似的速度继续生长，这表明ECFV可能是原生质生长的控制因素。
