Estrogen deprivation is associated with an increased morbidity due to osteoporosis and other metabolic disorders such as diabetes and obesity. Cr³⁺ has been shown to be beneficial with respect to carbohydrate, protein, and lipid metabolism. Therefore, the aim of this study was to investigate the effects of estradiol (E2) alone and E2 combined with Cr³⁺ on bone metabolism in ovariohysterectomized rats. Thirty-six 8-week-old female Sprague-Dawley rats were randomly divided into 6 groups after undergoing ovariohysterectomy. Body weight and plasma concentrations of calcium, phosphorus, parathyroid hormone, and osteocalcin were measured weekly. Both femurs and both tibiae were dissected to measure the percentage of the trabecular bone (BV/TV%). The final VarBW% in the control group was significantly higher (P<0.05) than those in the other groups. The BV/TV% of the tibia and that of the femur in the HE2 group were significantly higher (P<0.05) than those in the other groups. However, the percentage of the trabecular bone in the proximal metaphysis of the tibia in the HE2 group was significantly decreased (P<0.05) after Cr supplementation. The plasma concentration of calcium in the low-dose estradiol groups was significantly higher (P<0.05) than that in the high-dose estradiol groups. The plasma concentration of phosphorus fluctuated in different groups. The plasma concentration of phosphorus in the control group was the lowest (P<0.01) among all experimental groups. The calcium–phosphate product in the control group was the lowest (P<0.01) among all groups. The concentration of PTH in the HE2 group was significantly higher (P<0.05) than that in the control group, but there was no significant statistical difference (P>0.05) among the Cr, LE2, LE2+Cr, and HE2+Cr groups with respect to the concentration of PTH.

To Cite This Article: Kong LJ, Hsu TH, Wang HC, Chen KS and Lee WM, 2019. Effects of estradiol alone and estradiol combined with trivalent chromium on bone metabolism in ovariohysterectomized rats. Pak Vet J, 39(2): 278-284. http://dx.doi.org/10.29261/pakvetj/2019.005