Effects of age on expression of intestinal Ca²⁺ transporters and of renal 1,25(OH)₂D₃ metabolic enzymes in mice.

<p>A comparison of the expression levels of Ca²⁺ transporters (<b>A</b>) and 1,25(OH)₂D₃ metabolic enzymes (<b>B</b>) in four mo old mice after three mo of feeding on normal Ca²⁺ diet containing 63% glucose (from study 2) and in two mo old mice fed a normal Ca²⁺ diet containing 43% glucose for five wk (from study 1). All expression data were analyzed by real-time PCR using <i>EF1</i>α as a reference and normalized relative to levels seen in four mo old mice. Data are means ± SEM (<i>n</i> = 5–6 per group). Differences (<i>P</i><0.05) between means are indicated by asterisks. Expression of intestinal Ca²⁺ transporters decreases with age.