Evidences for spermatozoa toxicity and oxidative damage of cadmium exposure in rats

Background: Spermatogenesis is a complex series of differentiation process that can be interfered by toxic chemicals, heavy metals, heat, radiation, deficiencies of hormones and immunodeficiency. Materials and Methods: Fifteen male Wistar rats (10-12 weeks old) weighing 164-279 g were divided into three groups of four rats each. The rats in group A served as the control group and were treated with 2.5 mL kg-1 b.wt., daily, group B and C rats were given a single dose of 5 and 7 mg kg-1 b.wt., of cadmium chloride solution intraperitoneally. The protocol lasted for 8 weeks. Results: There was a significant (p>0.01) reduction in spermatozoa count, spermatozoa motility, percentage number of morphologically normal spermatozoa and a significant (p>0.01) increase in the percentage number of morphologically abnormal spermatozoa (headless sperm, rudimentary tail, curved tail, curved mid-piece) in animal models exposed to cadmium. There was a significant (p<0.05) difference in SOD, GSH, CAT and MDA activity in the groups of rats when compared to the negative control group. Conclusion: This study has shown that cadmium induces morphological and functional abnormalities on rat spermatozoa by reducing antioxidant status.