Histological study of the bone marrow mast cells in ovariectomized adult albino rats

ABSTRACT

Ten 90 days old female albino rats were utilized in this research aiming to study the bone marrow mast cells in ovariectomized adult albino rats in an attempt to clarify one of the possible underlying cellular causes of postmenopausal osteoporosis. These rats were equally classified into 2 groups [a control group and an experimental one]. Bilateral ovariectomy was performed to the rats of the experimental group. After 30 days of the ovariectomy, all the rats of the two groups were sacrificed. Their tibiae were dissected out carefully and their proximal parts were obtained and processed for light and electron microscope examinations. The spongy bone at the proximal tibial metaphysis of the ovariectomized rats appeared with few bone trabeculae. Numerous osteoclasts were observed in the examined sections. These cells appeared with multiple euchromatic nuclei and prominent nucleoli and their cytoplasm contained numerous mitochondria. The surrounding bone marrow contained numerous mast cells. Some of these cells were seen near the bone trabeculae. In conclusion, the concomitance between increased bone marrow mast cells number and osteoclasts number and activity with reduced bone trabeculae of the spongy bone of the proximal tibial metaphysis of the estrogen- deficient rats may suggest a role for mast cells in postmenopausal osteoporosis. So, regulation of mast cells activation may be a critical issue and a promising therapeutic approach in the treatment of this disease