酪蛋白磷酸肽(CPP)对生长期大鼠骨密度的影响

Effects of Casein Phosphopeptides(CPP) on bone mineral density in growing rats

探讨4种不同酪蛋白磷酸肽(CPP)的不同CPP/Ca比值对生长期大鼠骨密度的影响。选用4周龄雄性SD大鼠,按体重随机分为低钙组、补钙组和CPP加钙实验组(A,B,C,D四种CPP按CPP/Ca比值为1,2,4,分别设低、中、高3个剂量组),以灌胃方式给予补钙和CPP,12周后处死大鼠,取双侧股骨,称重,计算股骨指数;化学法测骨钙,双光能X线吸收法测骨密度。结果表明,4种CPP三个剂量组和补钙组大鼠骨密度均显著高于低钙组(P<0.01),其中C种CPP高剂量组的骨密度显著高于补钙组(P<0.05),其余各组CPP的骨密度也高于补钙组,但差异不显著。C种CPP在CPP/Ca比值为4时能显著促进大鼠钙的吸收和利用,提高股骨骨钙含量,增加骨密度,其他3种CPP增加骨密度的作用不显著。

It was studied that the effects of four casein phosphopeptides （CPP）, named A, B, C, D, and the different ratios of CPP to calcium on bone mineral density （BMD） in growing rats. Four weeks male Sprague-Dawley rats were divided into low calcium control group, high calcium group and different dose CPP plus calcium groups at the ratio of CPP/Ca 1, 2, 4. The calcium and CPP were given to rats by intragastric administration for 12 weeks, and the two femurs were collected and weighed. The femur calcium was measured by chemical analysis and the BMD by dual-energy X-ray absorptlometry. Compared with low calcium group, the BMD of rat femur significantly increased in the four CPP at different doses group and high calcium group, respectively （P〈0.01）. All the CPP groups had higher BMD than the calcium group, but only one （C） of CPP at the high dose had statistically significant difference （P〈0.05）. One CPP （C） at ratio of CPP/Ca 4 could significantly increase the femur BMD in rats, the same effects of other three CPP was not obvious.