Abstract
Bisphenol A (BPA) is a widespread endocrine disruptor known to cause reproductive toxicity. Melatonin has shown promise in ameliorating BPA-induced reproductive damage, but its effects on BPA-induced morphometric changes in reproductive tissues require further investigation. This study investigated the effects of combined melatonin and BPA administration on morphometry of male reproductive organs in Wistar rats. Twenty-four adult male Wistar rats were divided into four groups: control, BPA-treated (10 mg/kg/day), melatonin-treated (10 mg/kg/day), and BPA + melatonin-treated. After 45 days, testes, epididymides, and spermatozoa were analyzed for morphometric parameters. BPA significantly reduced epididymal and testicular tubular density compared to control (p < 0.05). Melatonin treatment alone increased epididymal germinal epithelial height and decreased luminal diameter (p < 0.05). The combined BPA + melatonin treatment showed the lowest epididymal luminal diameter (p < 0.05) and highest testicular tubular density. Spermatozoa head diameter was significantly reduced in the melatonin group compared to the BPA group (p < 0.05). The combined treatment group showed a significant decrease in entire sperm length compared to all other groups (p < 0.05). Melatonin administration mitigated BPA-induced morphometric anomalies in male rats, primarily by increasing testicular and epididymal tubular density and modulating epididymal luminal diameter. This study demonstrated morphometric effects of BPA and melatonin on male reproductive systems, but the molecular mechanisms remain unexplained. Future research should explore biochemical pathways and long-term reproductive impacts.