Pereira Maria de Lourdes, das Neves Ricardo Pires, Oliveira Helena, Santos Teresa Margarida, de Jesus Júlio Pedrosa
Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal.
Environ Health. 2005 May 27;4:9. doi: 10.1186/1476-069X-4-9.
Cr(V) species are formed during the intracellular reduction of Cr(VI), a ubiquitous environmental pollutant. In this study, the acute toxicity of a physiologically stable Cr(V) compound, CrV-BT (BT = bis(hydroxyethyl)aminotris(hydroxymethyl)methane) was investigated in the male reproductive system of sexually mature 60-day-old male ICR-CD1 mice.
Eight-week-old animals were subcutaneously injected daily with a dose of ca 8 micromol of Cr/mouse, during 5 days. The control group was injected with 0.5 mL of BT buffer. Testis and epididymis morphology was evaluated using light and transmission electron microscopy. Epididymal sperm counts, motility and acrosome integrity were also assayed using standard methods.
Seminiferous epithelium abnormalities were detected in the CrV-BT experimental group, including intraepithelial vacuolation, and remarkable degeneration of Sertoli cells, spermatocytes and spermatids. The premature release of germ cells into the tubular lumen was also evident. Histological evaluation of epididymal compartments revealed apparently normal features. However, the epididymal epithelium presented vacuolation. CrV-BT induced a reduction in sperm acrosome integrity. However, sperm motility and density were not significantly affected.
This in vivo study using a Cr(V) compound, provides evidence for the potential reproductive hazards caused on male reproductive system by species containing chromium in intermediate oxidation states.
六价铬是一种普遍存在的环境污染物,在细胞内还原过程中会形成五价铬物种。在本研究中,研究了一种生理稳定的五价铬化合物[CrV - BT](2 - )(BT = 双(羟乙基)氨基三(羟甲基)甲烷)对60日龄性成熟雄性ICR - CD1小鼠雄性生殖系统的急性毒性。
8周龄动物每天皮下注射约8微摩尔铬/小鼠的剂量,持续5天。对照组注射0.5 mL的BT缓冲液。使用光学显微镜和透射电子显微镜评估睾丸和附睾的形态。还使用标准方法检测附睾精子计数、活力和顶体完整性。
在CrV - BT实验组中检测到生精上皮异常,包括上皮内空泡化,以及支持细胞、精母细胞和精子细胞的明显退化。生殖细胞过早释放到管腔中也很明显。附睾各部分的组织学评估显示外观正常。然而,附睾上皮出现空泡化。[CrV - BT](2 - )导致精子顶体完整性降低。然而,精子活力和密度没有受到显著影响。
这项使用五价铬化合物的体内研究为中间氧化态含铬物种对雄性生殖系统造成的潜在生殖危害提供了证据。