Effects of estrogen and growth hormone on skeleton in the ovariectomized rat with hypophysectomy

The role of the growth hormone (GH) and 17beta-estradiol (E2) on bone mass and turnover was examined in ovariectomized rats. Administration of GH to the rats resulted in increased cortical bone formation, serum levels of osteocalcin and systemic growth. High or low doses of GH or E2 alone partially prevented cancellous bone loss but combined treatment of GH and E2 increased cancellous bone mass. These results suggested that the effect of GH and E2 on cancellous bone may be due to the anabolic effect of GH on bone formation and the suppressive impact of E2 on bone resorption.