Kalenga M, Henquin J C
Pediatr Res. 1987 Jul;22(1):45-9. doi: 10.1203/00006450-198707000-00012.
The effects of early protein-deficiency on lung development were studied in the rat. Newborn male rats were nursed in groups of eight. Control dams and pups received a 15% protein diet during the whole experiment. Test mothers only received 12 and 8% proteins from the 7th and the 14th day of lactation. Test rats fed a diet of 8% protein were weaned at 21 days and maintained on the low protein diet for 1 month. This caused a marked decrease in body weight gain, but lung/body weight ratio was not affected. Lung DNA and protein content, lung protein concentration, but not lung DNA concentration were decreased, suggesting the presence of fewer and smaller cells than in control lungs. Volume-pressure curves were performed on excised lungs. With air-filling, the curve obtained in rats fed a diet with 8% proteins was shifted downward and to the right, even when expressed as percent of maximal volume. Its exponential analysis assessed a decrease in lung compliance. In contrast, with saline-filling, the recoil pressure was decreased in rats fed a diet with 8% proteins. Both with air and saline-filling, the pressure at lung rupture was increased in malnourished rats. It is concluded that protein-deficiency from the neonatal period increases surface forces, decreases tissue elastic forces, and augments resistance of the lung to rupture.
在大鼠中研究了早期蛋白质缺乏对肺发育的影响。新生雄性大鼠以每组八只的方式进行哺乳。在整个实验过程中，对照母鼠和幼鼠接受含15%蛋白质的饮食。受试母鼠仅在哺乳期的第7天和第14天接受含12%和8%蛋白质的饮食。喂食含8%蛋白质饮食的受试大鼠在21日龄时断奶，并维持低蛋白饮食1个月。这导致体重增加显著下降，但肺/体重比未受影响。肺DNA和蛋白质含量、肺蛋白质浓度降低，但肺DNA浓度未降低，这表明与对照肺相比，细胞数量更少且体积更小。对切除的肺进行容积-压力曲线测定。充气时，喂食含8%蛋白质饮食的大鼠所获得的曲线向下和向右移动，即使以最大容积的百分比表示也是如此。其指数分析评估了肺顺应性的降低。相反，用生理盐水灌注时，喂食含8%蛋白质饮食的大鼠的回缩压力降低。无论是充气还是用生理盐水灌注，营养不良大鼠的肺破裂压力均升高。结论是，新生儿期的蛋白质缺乏会增加表面力，降低组织弹性力，并增强肺对破裂的抵抗力。
