Dietary vitamin D₃ restriction reduces serum 25(OH)D₃ and 1,25(OH)₂D₃ levels.

<p>Female BALB/c mice were placed on vitamin D₃ (VitD)-containing or -deficient diets from 3 weeks of age. At 8 weeks of age the female mice were mated with adult BALB/c male mice (fed vitamin D₃-replete diets). In (A), (B) and (C), serum 25(OH)D₃, 1,25(OH)₂D₃ and calcium levels (respectively) were measured in female and male 8 week-old offspring of these matings (n = 5 mice/group). In (D), 7-dehydrocholesterol levels were determined in the skin of vitamin D₃-deficient female and male mice. In (E), kidney CYP27B1 mRNA levels induced by vitamin D₃ deficiency in female and male mice are shown. In (F), kidney CYP27B1 and CYP24A1 mRNA levels induced by being male for vitamin D₃-replete (VitD+) and -deficient (VitD-) mice. For (A)–(F), data is shown as mean + SEM, with n≥3 mice/group, *p<0.05 between groups, #p<0.05 relative to levels in vitamin D3-replete (E) or female (F,G) mice.