2. Department of Medical Histology, Faculty of Medicine, Assiut University Assiut, 71516 Egypt.
Objective: There are evidences indicating that diazepam administration inhibits cell proliferation both in vitro and in vivo. The benefits of melatonin against diazepam-induced proliferative activity, morphological and level of testosterone changes were investigated in this study.
Materials & methods: Three equal-sized groups of male rats [control, diazepam (3 mg/kg) and diazepam plus melatonin (10 mg/kg)] were used. Levels of testosterone hormone in the serum were measured. Cell proliferation was detected by autoradiography and the morphological alterations were investigated.
Results: Results documented decreased both 3H-labelling index (proliferative activity) and the levels of testosterone with marked histopathological alterations in the seminiferous tubules of diazepamadministered rats versus those of controls. When melatonin was given to diazepam-administered rats, it stimulates the decrease of labelling index, restored the levels of testosterone and preserves the alterations and number of different germ cell types in all stages of the seminiferous tubules.
Conclusion: These results suggest long-term hazard in use of drugs such as diazepam may be toxic and damage terminates in complex testes dysfunction and infertility. Furthermore, melatonin may be useful in combating testes injury resulting from hazard and/or repeated diazepam administration.
Keywords: Melatonin, diazepam, 3H-labelling index, seminiferous tubule