Prostatic assessment in rats after bilateral orchidectomy and calcitonin treatment

Abstract

Objective: Bilateral orchidectomy is widely used as a treatment in patients with metastatic prostatic cancer, but post-orchidectomy osteoporosis is a common sequel which is commonly treated by postoperative calcitonin injection. Since the increase in the invasiveness of malignant prostatic cells has been attributed to the use of calcitonin, this study was aimed to elucidate the effect of calcitonin on the structure of the prostate after orchidectomy in rats used as mammalian model.

Methods: A total of 84 adult male albino rats were divided into three groups: Group 1 (12 control rats); Group 2 (36 rats subjected to bilateral orchidectomy); Group 3 (36 rats subjected to bilateral orchidectomy and injected subcutaneously with calcitonin (5 µg/kg) every other day. Six animals of Group 2 and 3 were sacrificed two, four, eight, sixteen and twenty four weeks after orchidectomy. The prostates were removed and processed for morphometric measurements by using the image analyzer computer system.

Results: The present study demonstrated a decrease in the height and apoptosis of the epithelial lining of the prostatic acini. There was also an increase in the interacinar fibromuscular stroma. However, calcitonin administration following orchidectomy limited these changes.

Conclusion: Bilateral orchidectomy produced time related atrophic changes in the prostate, while a simultaneous administration of calcitonin inhibits the development of these atrophic changes.