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Summary. Ovariectomy is one of the most common ways of inducing experimental osteoporosis, since there are no meaningful differences in bone behavior between surgical and natural menopause. Because ovariectomized rat still represent the “gold standard” in studies of postmenopausal osteoporosis, the present study focuses on an animal model of osteoporosis which we developed for researching the effects of medicament and non-medicament treatment of this bone disease. Experiments were conducted on a total of 18 female Wistar rats aged fourteen weeks, randomly divided into three experimental groups: intact (INT) group and two groups of ovariectomized (OVX) animals (OVX I and OVX II), consisting of 6 animals each. Animals are ovariectomized using a ventral approach, which in our experience is more favorable than the midline dorsal skin incision or double dorsolateral approach, both of which are also commonly used for inducing experimental osteoporosis. The OVX I group consisted of bilateral ovariectomized females sacrificed six weeks after ovariectomy, while OVX II was sacrificed eleven weeks after ovariectomy. The group of intact, un-operated control animals (INT group) was sacrificed after eleven weeks together with animals of the OVX II group. Blood samples for measurement of serum alkaline phosphatase, osteocalcin, calcium and phosphorus level are collected from animals of the INT and OVXI group after six weeks and from animals of INT and OVX II groups after eleven weeks. Histological analyses were done on tibia while biomechanical measurements were done on the femurs of animals from INT, OVXI and OVX II groups. In animals of the OVX I group, levels of alkaline phosphatase, osteocalcin, phosphorus and calcium were statistically significantly increased (p |
