Peterson C A, Baker D H, Erdman J W
Division of Nutritional Sciences, University of Illinois, Urbana 61801, USA.
J Nutr. 1996 Jan;126(1):259-65. doi: 10.1093/jn/126.1.259.
The effect of altering the dietary Ca:P ratio during critical points of growth (based on reproductive and skeletal age) on kidney calcification in female rats was investigated. Groups of weanling animals were fed one of three nutritionally complete but calcium-altered diets (0.25, 0.5 or 1.0 g Ca/100 g diet) from 4 to 12 wk of age (Phase 1). Phosphorus concentration remained constant at 0.4 g/100 g diet resulting in Ca:P molar ratios of 0.48, 0.96 and 1.92, respectively. During Phase 2, the same animals within each diet group were then rerandomized into one of the above diets and fed for an additional 25 wk. Each group contained five rats. The data from the nine treatment groups were analyzed statistically using a two-way ANOVA (Phase 1 dietary Ca level by Phase 2 dietary Ca level). The level of dietary Ca during Phase 1 only exerted a significant influence on kidney Ca accumulation. Rats fed the two lower dietary Ca levels, and hence lower dietary Ca:P molar ratios, during Phase 1 had two- to threefold greater kidney Ca concentration and kidney ash Ca concentration than rats fed the diet with the highest dietary Ca level (1.92 Ca:P molar ratio) during Phase 1, regardless of the Ca intake during Phase 2. In contrast, the dietary Ca:P molar ratio during Phase 2 had little effect either positively or negatively on the kidney Ca concentration that had been established during Phase 1. The results indicate that dietary-induced nephrocalcinosis in female rats is irreversible and is induced primarily before the completion of adolescence (approximately 12 wk of age) in Sprague-Dawley female rats.
研究了在生长关键期（基于生殖和骨骼年龄）改变饮食中钙磷比，对雌性大鼠肾脏钙化的影响。将断奶动物分组，从4周龄至12周龄（第1阶段）喂食三种营养完全但钙含量不同的饮食之一（0.25、0.5或1.0 g钙/100 g饮食）。磷浓度保持恒定，为0.4 g/100 g饮食，导致钙磷摩尔比分别为0.48、0.96和1.92。在第2阶段，每个饮食组中的相同动物再随机分为上述饮食之一，并额外喂食25周。每组包含5只大鼠。使用双向方差分析（第1阶段饮食钙水平×第2阶段饮食钙水平）对九个处理组的数据进行统计分析。仅第1阶段的饮食钙水平对肾脏钙积累有显著影响。在第1阶段喂食两种较低饮食钙水平（因此饮食钙磷摩尔比也较低）的大鼠，其肾脏钙浓度和肾脏灰分钙浓度比在第1阶段喂食最高饮食钙水平（钙磷摩尔比为1.92）的大鼠高两到三倍，无论第2阶段的钙摄入量如何。相比之下，第2阶段的饮食钙磷摩尔比对第1阶段已确定的肾脏钙浓度几乎没有正向或负向影响。结果表明，饮食诱导的雌性大鼠肾钙质沉着症是不可逆的，并且主要在青春期结束前（约12周龄）在斯普拉-道来雌性大鼠中诱发。
