Orchidectomy Models of Osteoporosis

Long considered a disease of post-menopausal women, osteoporosis is increasingly being recognized among the growing population of elderly men. Androgen deficiency may be associated with an increase of bone resorption in elderly men and so, with remodeling imbalance and fracture risk. It is firmly established that androgen withdrawal induced by orchidectomy (ORX) results in decreased bone mass in animal models especially in rodents. The mature rat is the model of choice. Skeletal effects of ORX in rats have been studied at the tissular and cellular level. It induces a decrease of BMD and BV/TV with microarchitecture alterations due to an increased bone remodeling. The present chapter focuses on the ORX surgery in rats and mice.