The aim of this part of study is the determination, if the administration of Calcitonin affects the bone bending strength in ovariectomized rats. Calcitonin was administered subcutaneous (s.c.) in 0.2 ml on alternate days 3 days in week. In volume 0.2 ml there are 3 units of Salmon Calcitonin. This work is founded on the co-operation of Czech Technical University in Prague, Faculty of Mechanical Engineering, Laboratory of Biomechanics of Man and the First Faculty of Medicine, Charles University, Prague.