Effect of metronidazole on spermatogenesis, plasma gonadotrophins and testosterone in adult male rats

Metronidazole and its derivatives are drugs with both antiprotozoal and antibacterial effects. The reproductive toxicity of metronidazole has been shown in some studies. This study was carried out to investigate the effect of metronidazole on spermatogenesis in male adult rats. Twenty-four Wistar male rats were randomly assigned to three groups. Animals in group I (Control group) received water and those in groups II and III received metronidazole with doses of 200 and 400 mg/kg/day, respectively for 60 days. Different varieties of germ cells, seminiferous tubule epithelium, spermatogonia, primary spermatocytes and spermatids were quantitatively evaluated. Also using radioimmunoassay technique plasma follicle-stimulating hormone (FSH), lutuneizing hormone (LH), and testosterone were measured. In the 200 and 400 mg/kg groups, there were significant drop in the testes and accessory sex organ weights, plasma concentrations of LH, FSH and testosterone with massive degeneration of germ cells. Metronidazole has a suppressive influence on both spermatogenesis, plasma level of gonadotropins and testosterone in the male rats.