P-251: Effects of Indomethacin on Postnatal Development of Mouse Testes

Objective: Indomethacin is a non-selective cyclooxygenase (COX) inhibitor that is commonly administered to extremely low gestational age neonates for symptomatic patent ductus arteriosus. It suppresses prostaglandins which modulate growth and secretion of various hormones. We examined the hypothesis that early postnatal administration of Indomethacin may influence growth and development of testes in neonatal mice. Materials and Methods: The mice were acclimatized for seven days prior to coupling and were housed in an air conditioned animal house at 22 ± 2ºC with exposure to 10–12 hours of daylight. Day zero of pregnancy was determined by vaginal plug test. In this study, mice pups received intraperitoneally injection of 25, 50 and 100 mg/kg Indomethacin which was dissolved in 0.09% NaCl on the day of birth. After pup’s delivery, male pups were sacrificed on day 35 and testes were removed, fixed in 10% neutral buffered formalin and embedded in paraffin wax. Serial sections (5μm) of the medullary area were obtained in each group and stained with hematoxylineosin. The sections were observed under light microscopy. For all experiments, at least 6 to 8 replicates were performed. The data were analyzed statistically using analysis of variance (ANOVA). A level of (p<0.05) was accepted as significant. Results: Our results indicated that intraperitoneally injection of 25, 50 and 100mg/kg Indomethacin decreased the number of spermatogonia, spermatocyte and sperm in seminiferous tubule. The number of seminiferous tubules decreased in comparison to control (p<0.05). Conclusion: These results provide evidence for the involvement of prostaglandins in the regulation of development and suppressing the growth of testis in the sucking mice. Therefore, early postnatal exposure to Indomethacin as a prostaglandins inhibitor may further exacerbate postnatal growth restriction of testis and ability to cope with stress.