Evaluation of in vivo reproductive toxicity of potassium chromate in male mice

Abstract

To evaluate the effects of potassium chromate on mice sperm cells after a short-term exposure, male ICR-CD1 mice were administered with 5 or 10mgK(2)CrO(4)/bw for 4 consecutive days. One group of mice was sacrificed at day 5, starting from the beginning of the experiment and another group was sacrificed at day 35. Testis and epididymis histology was evaluated by light microscopy and testicular cells populations were evaluated by flow cytometry (FCM). Spermatozoa were collected from the epididymis and their morphology and several functional parameters (density, motility, viability, mitochondrial function, acrosome integrity) were evaluated. Furthermore, DNA fragmentation and chromatin status of sperm cells were assessed at both experimental periods. Besides a reduction in seminiferous tubules diameter, exposure to potassium chromate did not induce further histopathological changes in mice testis or epididymis. These results were supported by the analysis of testicular cellular subpopulations by FCM. Concerning spermatozoa morphology, an increase in the percentage of multiple abnormalities and a decrease in the percentage of normal spermatozoa were found at days 5 and 35, respectively. Although spermatozoa mitochondrial function or viability was not affected, its motility was significantly reduced by potassium chromate exposure at both experimental periods. A decrease in acrosome integrity was found in mice injected with 10mgK(2)CrO(4)/bw after 35 days. Exposure to potassium chromate did not affect either DNA fragmentation or chromatin susceptibility to acid denaturation of sperm cells. In this work, we were able to show the effects of potassium chromate on spermatozoa physiological parameters such as motility, morphology and acrosome status and also demonstrate that the doses tested did not induce DNA damage to sperm cells after one spermatogenic cycle.