Estrogen effects on interleukin-1 expression in alveolar bone remodeling of osteoporotic rats / 中国组织工程研究

ABSTRACT

BACKGROUND:Currently rats are the most frequently used animal for the models of osteoporosis and ovariectomized rat models have been widely applied due to ovariectomized female rats are similar to human body in bone mineral density changes and response after estrogen administration. OBJECTIVE:To establish rat models of osteoporotic tooth extraction wound healing, and to investigate the effect of estrogen on the interleukin-1 expression and distribution in the remodeling of osteoporotic alveolar bone. METHODS:Sixty-five purebred female rats, 3 months old, were randomly divided into two groupsosteoporosis model group (n=40;ovariectomy under general anesthesia) and sham operation group (n=25;fat tissue around ovary was removed). After 8-week feeding, osteoporosis models were established and the left upper molar was pul ed out under general anesthesia. Histomorphomeric parameters test was performed on the jaw bone. In osteoporosis model group, 15 rats were randomly selected to give subcutaneous injection of estradiol benzoate, as the estrogen treatment group. Immunohistochemical method was applied to observe the interleukin-1 expression in the remodeling of osteoporotic alveolar bone. RESULTS AND CONCLUSION:After ovariotomy, the amount of trabecula decreased and the medul ary cavity of the bone became larger, the jaw bone intensity decreased. After administration of estrogen, the positive expression of interleukin-1 was reduced as compared with osteoporosis model group. Experimental findings indicate that, osteoporosis can be detected in Sprague-Dawley female rats aged 3 months at 8 weeks after ovariotomy, and administration of estrogen can obviously decrease interleukin-1 positive expression in the remodeling of osteoporotic alveolar bone.