Histological effects of melatonin on testes in pinealectomized and normal albino rats


In the present study, the histological effect of melatonin (MEL) on pinealectomized (PINx) and normal rats’ testes was investigated. Thirty six adult male rats were used in this study. The rats were divided into six experimental groups as follow: 1¬¬st control group; 2nd sham-operated surgery rats group; 3rd PINx rats group, 4th PINx rats+MEL (60 mg / Kg diet) group; 5th control rats+MEL (60 mg / Kg diet) group; and 6th control rats+MEL (120 mg / Kg diet) group and the treatments were continued for six weeks. The result showed mild histological changes in testicular tissue of sham-operated surgery rats, like shrinkage and atrophy of seminiferous tubules (STs) and weakness in spermatogenesis. While, in PINx rats revealed regressive changes in testicular tissue, like sever degeneration, vacuolation and necrosis in germinal epithelium and no spermatogenesis. But as PINx rats were given MEL 60 mg/kg diet, the testicular structure and function were recovered, whereas, in normal rats were given MEL 60 and 120 mg/kg diet, the result show sever vacuolation and sloughing of spermatocytes inside STs lumen and no spermatogenesis at rats+60 MEL and mild edema with well development of germinal epithelium and spermatogenesis at rats+120 MEL. In conclusion, the deficiency of MEL level leads to change in histology and physiological activities of rat testes.