Bone histomorphometry evaluate the effect of the adminstration method and the dose of glucocoticoid on metabolism of bone tissue in rats

Objective To study the the effect of the adminstration method and the dose of glucocoticoid on metabolism of bone tissue in rats.Methods 4 months old Sparague Dawley femal rats were randomly divided into three groups:Group A was treated with normal sodium intragastric administration as control 5 ml/kg·d;Group B was administrated at low-dose predispose by intragastric administration 2 ml/kg·d;Group C was administrated at predispose 6 ml/kg·d.All were treated once a day for 18 weeks.After 18 weeks,all rats were killed and their femur neck were processed undecalcifying sections and measured by automatic image-analysis system for bone histomorphometry.Results Compared with group A,no marked changes appear in the index of group B.The TbAr,Tb.N,Tb.Th of group C has decreasesd significantly,but Tb.Sp increase singnificantly.Conclusion The occurrence of glucocorticoid-induced osteoporosis was closely related to the dose of glucocorticoid.The femur neck of rats is important model to study osteoporosis.