Zamenhof S
Biol Neonate. 1981;39(1-2):45-51. doi: 10.1159/000241391.
Maternal 'efficiencies' in production of fetal tissue, especially brain tissue, were studied in controls and in chronically (9 generations) undernourished rats. These 'efficiencies' were formulated as the ratio of a neonatal parameter (body) weight, brain weight, DNA, or protein) to the food consumed during pregnancy. Mean or total values (for the entire litter) of the above parameters were used in computation of the above ratios. It was found that all these ratios were highly significantly lower for control animals than for undernourished. The gain in maternal body weight (postpartum versus day 0 of pregnancy), i.e., nutrient storage, was found to be significantly lower or even negative in the undernourished group, but increased through generations. We interpret these results as follows. Undernourished animals mobile their nutrient reserves, avoid deamination of essential amino acids, and improve their intestinal absorption of nutrients; thus, they are more efficient than normal animals, even though the latter may produce more fetal tissue. These improvements suggest inducible enzymes. Individual mothers in each group vary considerably in their efficiency; the most efficient undernourished mothers may produce offspring that escape undernutrition, or, in the control group, offspring with outstanding values of brain and body parameters.
在对照组和长期（9代）营养不良的大鼠中，研究了母体在产生胎儿组织，尤其是脑组织方面的“效率”。这些“效率”被定义为新生儿参数（体重、脑重、DNA或蛋白质）与孕期消耗食物量的比值。上述参数的平均值或总和值（针对整个窝仔）用于计算上述比值。结果发现，所有这些比值在对照动物中都显著低于营养不良的动物。营养不良组母体体重增加（产后与妊娠第0天相比），即营养储存，显著更低甚至为负，但随着代数增加而增加。我们对这些结果的解释如下。营养不良的动物动用其营养储备，避免必需氨基酸脱氨，并改善其肠道对营养物质的吸收；因此，它们比正常动物更高效，尽管后者可能产生更多的胎儿组织。这些改善表明存在诱导酶。每组中的个体母亲在效率上差异很大；最有效的营养不良母亲可能会生出逃脱营养不良的后代，或者在对照组中，生出脑和身体参数值出众的后代。
