The morphology of paca (Cuniculus paca) testis with high dose of letrozole an aromatase inhibitor / La morfología del testículo de paca (Cuniculus paca) con altas dosis de letrozol, un inhibidor de la aromatasa

SUMMARY: The study reported the influence of the high and acute dose of Letrozole on the testis morphology in paca (Cuniculus paca), an aromatase inhibitor that reduces the endogenous estrogen, the essential hormone for spermatogenesis. Morphological changes were observed in seminiferous epithelium with germ cells with apoptotic characteristics and presence of vacuoles and nuclei in pycnose.

RESUMEN: El objetivo de este estudio fue analizar la influencia de una dosis alta de Letrozol en la morfología de los testículos de la paca (Cuniculus paca), un inhibidor de la aromatasa que reduce el estrógeno endógeno, la hormona esencial para la espermatogénesis. Se observaron cambios morfológicos en el epitelio seminífero con células germinales con características apoptóticas y la presencia de vacuolas y núcleos en picnosis.

Seminiferous epithelium of rats with food restriction and carbon tetrachloride-induced cirrhosis

OBJECTIVE: Analyze the changes in the seminiferous epithelium in rats with carbon tetrachloride-induced cirrhosis (CCl4). MATERIALS AND METHODS: Forty-eight male Wistar rats aged 45-50 days, weighing 150-180 grams were used. Twenty-two rats underwent CCl4-induced cirrhosis with CCl4 0.25 mL/Kg weekly intragastrically once a week, during 10 weeks. Additionally, they had a 44 percent food restriction diet (Group 1). The control group was divided in two subgroups: 13 rats had a 44 percent food restriction diet and no CCl4 (Group 2) and 10 rats were not submitted to CCl4 or food restriction (Group 3). After 10 weeks, the rats were sacrificed and liver sections were collected for histological analysis. The testicular analysis was carried out to evaluate the frequency of tubules in stages VIII and XIV. RESULTS: The mean rates of stage VIII in animals with food restriction plus CCl4-induced cirrhosis and food restriction without CCl4 were significantly different from animals without either food restriction or CCl4 (18.1 ± 5.5 percent, 20.5 ± 2.5 percent and 13.4 ± 3.5 percent, respectively, p = 0.002). The mean rate of stage VIII in rats with cirrhosis was not significantly different from rats without cirrhosis (18.1 ± 5.5 percent and 17.4 ± 4.6 percent respectively). The mean frequency of stage XIV in rats with cirrhosis was significantly greater than rats without cirrhosis (4.7 ± 2.3 percent and 6.8 ± 1.9 percent respectively, p = 0.027). CONCLUSION: Animals with CCl4-induced cirrhosis and food restriction have shown alterations in spermatogenic cycle that were not seen in rats without CCl4-induced cirrhosis and food restriction.

5-fluorouracil (5-FU) induces the formation of giant cells and sloughing of seminiferous epithelium in the rat testis.

The chemotherapeutic agent, 5-fluorouracil (5-FU) has been widely used in the treatment of a variety of cancers. Its effect on the testis has not been substantially studied. Present study was conducted to evaluate the gonadotoxicity of 5-FU in male albino rats. Animals were injected with single dose of 5-FU (10, 50 and 100 mg/kg, i.p.) and sampled on 1, 3, 15 and 30 day post exposure. Animals were anaesthetised, testes were perfusion fixed by Bouin's fluid. Five micron thick paraffin sections were stained with haematoxylin and eosin. Slides were screened for the incidence of partially and extensively sloughed tubules. Data were analysed by Mann Whitney 'U' test. Only 100 mg/kg induced multinucleated cells on 3rd day. All doses of 5-FU induced sloughing of the seminiferous epithelium. Maximum number of partially sloughed tubules were seen on third day. Partial sloughing was not dose dependent except on 15th day. The extensive sloughing was dose dependent except on 30th day. The result indicates that all the doses of 5-FU tested in this study cause sloughing of epithelium and only 100 mg/kg induces the formation of giant cells on third day.