ULTRASTRUCTURAL STUDIES OF SPERMIOGENESIS IN RABBIT EXPOSED TO CHRONIC FLUORIDE TOXICITY

Objective-To address the role of fluoride in causing defects to sperma tids and epididymal spermatozoa. Methods-Male rabbits were treated wit h 10 mg NaF/kg body weight daily for 18 months and maintained under id entical laboratory conditions along with the control rabbits net given NaF Testis and epididymis (caput) were investigated for ultrastructur al details of spermatids and spermatozoa. Results-A wide variety of st ructural defects were observed in the flagellum, the acrosome, and the nucleus of the spermatids and epididymal spermatozoa of fluoride-trea ted rabbits. Abnormalities included absence of outer microtubules, com plete absence of axonemes, structural and numeric aberrations of outer dense fibers, breakdown of the fibrous sheath, and structural defects in the mitochondria of the middle piece of the flagellum. Detachment and peeling off of the acrosome from the flat surfaces of the nucleus were also observed. Conclusion-The abnormalities observed render the s perm nonfunctional and ineffective, and thus there is a possible role of fluoride in causing infertility.