Synopsis
The effects of zinc deficiency on plasma calcium and ionized calcium concentrations were exam-ined in rats. We monitored plasma concentrations of calcium, ionized calcium (Ca
2+), parathyroid hormone (PTH) and ionized magnesium (Mg
2+) in male 4 week-old Sprague-Dawley rats, that were divided into three groups: zinc-deficient (Zn-Def), low-zinc (Low-Zn), and control pair-fed to Zn-Def (Pair-fed) groups, for 28 days. Comparing to Pair-fed rats, plasma calcium and Ca
2+ con-centrations of Zn-Def rats were found to be significantly lower after 4, 14, 21, 28 days of feeding. There was no significant change of the plasma Mg
2+ concentration among three groups. Comparing to Pair-fed rats, the plasma PTH concentration in Zn-Def rats tended to be higher after 21 days of feeding, and significantly higher after 28 days of feeding. The results suggest that zinc deficiency causes to decrease plasma calcium and Ca
2+ concentrations prior to an increase of the plasma PTH concentration.
Key words: zinc, calcium, parathyroid hormone, ratsy