Lithium effect on testicular tissue and spermatozoa of Viscacha (Lagostomus maximus maximus). A comparative study with rats

We investigated the effect of lithium chloride administration (Sigma): 1 mm ol/kg b.w. i.p./day for 35 days on the testes and sperm of viscacha (Lagost omus maximus maximus), a nocturnal rodent found only in the pampas of Argen tina. The histological study showed that hypospermatogenesis and the sperm number per mt decreased markedly in comparison with the controls (treatment group: 315 x 10(6) +/- 77 x 10 (6); control group: 693 x 10(6) +/- 39 X 10 (6), Means +/- SEM, Student's t-test: p < 0.05). The sperm motility and via bility were also affected. Under the same treatment, the testicular tissue and the sperm of rats were not damaged. Moreover, lithium induced these cha nges when the plasm levels were within the therapeutic range in humans. Our results provide evidence for the claim that viscacha testes and sperm reac t Very sensitively to low doses of lithium, whereas these concentrations do not produce damage in rats.