Effects of lithium carbonate on rat seminiferous tubules: an ultrastructural study

Lithium salts are commonly used for treatment of bipolar disorder but prolonged treatment with therapeutic doses induces substantial toxic effects. In the present study we examined the effects of lithium carbonate on the ultrastructure of rat seminiferous tubules. Rats were exposed to lithium carbonate at doses of 35 mg/kg/day for 21 days. After lithium treatment, the tunica propria widened and folded together with convolutions of the basement membrane, myoid cells and lymphatic endothelium. In the seminiferous epithelium loss of germ cell attachment and appearance of expanded intercellular spaces between spermatogenic cells were observed. Early stages of spermatogenic cells showed nuclear protrusions or swellings because of an extensive enlargement of the outer nuclear membrane. Round spermatids exhibited abnormally shaped acrosomes and dilation of the subacrosomal space. Many abnormal, degenerated late spermatids with random orientation were seen towards the basal and adluminal compartments of the seminiferous epithelium. In addition, spermatids exhibited alteration in F-actin bundle ectoplasmic specialization and contained many mitochondria-associated granular bodies.